BOSTON (CBS) – Several colleges in Boston were placed on lockdown after a student reported possible shots fired near Simmons University and Boston Latin School on Thursday, though the area has since been deemed safe. Boston Police tell WBZ-TV the scare was actually caused by the echo of balloons popping in the area.

Emmanuel College tweeted Thursday just before 3 p.m. urging anyone on campus to shelter in place, saying “this is not a drill.”

Simmons sent a community alert telling anyone on campus to barricade their door and hide and avoid windows. Mass Art was also on lockdown.

“Run, if option. Avoid campus. Wait for instructions,” the Simmons alert said.

The frightened students scrambled to protect themselves any way they could.

“There was like 20 of us in one bathroom so we were trying to like decide what to do.” Simmons student Devynn Ledgard said. “It was the scariest thing I’ve ever experienced.”

Just before 3:15 p.m., Simmons sent a second alert saying an all clear has been given.

At approximately 2:36 pm, a Simmons University student reported hearing sounds that she thought resembled shots fired. Out of an abundance of caution, a lockdown was ordered. Boston Police conducted a thorough search of the academic campus and found no evidence of any shot being fired. The All Clear was issued at 3:09 pm.

A spokesperson for Simmons University says the student did the right thing by reporting the incident.

Boston Latin was put into safe mode between 2:45 and 3:38 p.m. About 200 students were inside the building at the time.