At least four police officers have been shot in Philadelphia, officials have said.
A police spokesperson said at least one gunman was shooting at officers in the Nicetown area of the Pennsylvania city.
Footage shows a significant police presence, with dozens of police cars and armed officers.
Temple University tweeted that part of the institute was on lockdown and urged people to avoid the area.
The account posted: “Shots fired reported at 1500 Block Erie Av at Health Sciences Center Campus. Use caution. Avoid the area. Police are responding.”
It added: “Lockdown is in effect for Health Sciences Center Campus. Seek shelter. Secure doors. Be silent. Be still. Police are responding.”
The Bureau of Alcohol, Tobacco, Firearms and Explosives said a number of its agents are on the scene.
Source: SKY NEWS