A man who was out jogging is believed to have been the cause of a lockdown at West Broad Street Elementary School in Franconia on Thursday afternoon, police said.

The school was placed on lockdown at about 1:40 p.m. after three fourth-grade students on the school's playground reported seeing a man in a black sweater and black-hooded mask with a gun along a nearby tree line.

Franconia Township Police Chief Joseph Kozeniewski said authorities were "confident" that the children had mistaken the unidentified jogger for the armed person.

"We are not sure where [the children] came up with the idea of a man carrying a gun," Kozeniewski said.

The neighborhoods and streets adjacent to the 530 student, K-5 school were cordoned off as North Penn Tactical Response units swarmed into the area. The school's principal sent an email notification to parents informing them of the lockdown.

While searching nearby neighborhoods, police found a black sweatshirt hanging on a shrubbery outside a home. The sweatshirt was associated with the man described by students.

"We learned that there was a man returning from jogging on a trail not too far from the school. He said he was in the area at that time," Kozeniewski said.

They knocked on the door of the home and interviewed the sweatshirt's owner, who was described as "very, very cooperative." The man had returned from his jog and left the sweatshirt outside.

"Putting two and two together, we came up with the conclusion" that the jogger was the cause of the alarm, Kozeniewski said.

Kozeniewski said the students did the proper thing.

"They immediately notified the staff and the principal of the school. Upon quickly assessing the situation, they quickly put the school in lockdown and notified Franconia Township Police," Kozeniewski said. 

He said "within minutes" numerous officers from Franconia Township Police and neighborhood departments responded with the suspicion that there was an armed person within proximity of West Broad Street Elementary. 

"During the entire episode, the school was on lockdown. We had officers inside that building, and the children did a wonderful job, as well as the teachers and staff, in keeping the school secure so that no one was coming in or going out," Kozeniewski said.  

He said the lockdown was "very precise." Everyone was safe and no one was hurt, he said.

"I want to praise these three young people for doing the right thing. They weren’t sure. They said something didn’t look right. They did the right thing for reporting it immediately to teachers," he said.

Kozeniewski said it was a "good wakeup call" for law enforcement. 

"As far as the police, EMS and ambulance response, it was a good learning process that, fortunately, turned out very, very well, from something that, from the initial outset, could have been something that would have not been a good thing," he said.

"This gave us a good assessment of  how quick our response is, and how quick we can get a tactical team formed," Kozeniewski said. "These are all things in our breakout sessions that we need to look at: How good was this? and Where need to improve? Overall, the response and cooperation was top notch."

North Penn Tactical Response Team was assisted by Franconia Township Police, Souderton Police, Perseverance Fire Co. Fire Police, and canine units from Upper Merion Township, Plymouth Township and Whitemarsh Township.

Kozeniewski likened Thursday's event to a drill without the drill.

"One of the downsides of having practice where everybody knows it is not for real is this could be for real," he said. "All the way through, we had the impression that this may be a real thing here and we have to go by the book and work hard on this. This is not one where it's an exercise."

The school's dismissal was delayed by 20 minutes, until 3:40 p.m. The investigation ended around 3:30 p.m.

Souderton Area School District Superintendent Fred Johnson said the district will also debrief and look at its procedures. School district procedures and policies were rewritten about two years ago by Assistant Superintendent Frank Gallagher, Johnson said.

"We'll see what went well, what didn't go as well as it should. We will do a similar process at the district," he said.

Johnson said the parents, teachers and administrators of Souderton Area School District live with the notion daily that something tragic could happen in the district.

"We worry about buses and transportation every day. We make our plans, but one of the things is, we are always aware that something like this could happen," he said, referencing incidents like Sandy Hook. "We have to set that aside so we can function, but it never ever leasve our mind that something like this could occur."

Johnson said parents, and teachers, will be the frontline individuals to address Thursday's issue with students. He said resources beyond teachers talking to students will be available. 

"It's always with us," Johnson reiterated. "It never leaves us." 

Earlier story and updates below.

Update 3:10 p.m.: A growing number of parents have gathered outside the police cordon to pick up their children. School buses are expected to arrive at the school for dismissal on schedule.

One parent, Maureen Dennis, of Souderton, thought the school district responded well to the event.

"I think in light of recent events, it helped things," she said. "They take it more seriously."

Dennis theorized that maybe the children mistook the suspect for an elderly individual from Lion's Gate who wasn't of his or her right mind.

"It's more annoying than scary," Dennis said. "I just want to get my kids out."

Souderton Police Chief James Leary said he believed the report of the armed subject was unfounded and that authorities at the scene are beginning to demobilize.

Update 2:40 p.m.: Souderton Area School District superintendent Fred Johnson said that a student on the playground at recess reported seeing an individual wearing a ski mask and holding a gun.

"There is nothing now to substantiate the student's claim," Johnson said. "Nobody is in harm's way."

Johnson said it was "nice to know that our first responders are so quick and dedicated to the task."

The K-5 school has about 530 students.

Earlier story below.

A police tactical team is staging near West Broad Street Elementary School in Franconia following a report of an armed subject in the vicinity of the school, according to the Breaking News Network.

In an email to parents, school principal Marianne Boyd said the school had been placed on lockdown at about 1:40 p.m. in response to a "suspicious individual" who "was observed at a distance from the playground."

Police had taken charge of the search for the individual, Boyd said. Students and faculty were awaiting an "all clear" notification from the police, and a normal dismissal was expected. 

The North Penn Tactical Response Unit is at the scene and is said to be searching a wooded area near the school.

West Broad Street is closed between Cowpath Road and Hunsberger Lane.

A reporter has arrived at the scene and is gathering additional information.

This is a developing story.