At least one person has been injured and one person arrested following a shooting near the National Security Agency headquarters in Maryland, local media reports.
Police responded to the shooting at the NSA's Fort Meade campus after a black SUV rammed into a barrier.
Within 90 minutes, the NSA said there was no ongoing security threat and the situation was under control.
Cheryl Phillips, Fort Meade Garrison spokesperson, confirmed one person was injured in the shooting and was taken to hospital.
On Twitter, FBI Baltimore wrote: "The FBI is aware of the incident at Fort Meade and we are sending personnel to respond at this time."
It later confirmed the incident had been "contained".
The incident at Fort Meade has been contained. We have no further updates at this time.
— FBI Baltimore (@FBIBaltimore) February 14, 2018
The US President Donald Trump has been briefed after the shooting, the White House confirmed.
A White House Statement read: "Our thoughts and prayers are with everyone that has been affected."
An aerial image, captured from a WRC-TV helicopter, shows police and fire response vehicles outside the NSA gates. Bullet holes can be seen in the SUV's front window, and the air bags have been deployed.
A man appears to be handcuffed and surrounded by police officers responding to the shooting.
According to Fox5, the incident happened close to the visitors' gate at around 7.15am local time (12.15pm Irish time).
The National Security Agency is an intelligence agency of the US Department of Defence.
In March 2015, two people tried to drive their SUV through the NSA's gates, and were shot at by officers when they refused to stop.
One of the vehicle's occupants was killed.