More than a dozen people died on Monday morning after at least one gunman opened fire at a Navy yard in Washington, D.C.

The shooting took place in the cafeteria and hallway at the Washington Navy Yard. One of the shooters, Aaron Alexis, died after engaging in a shootout with police, but there is another possible gunman who may be on the loose, police said. The death toll now stands at 13.

Helicopters, SWAT teams, the FBI, U.S. Capitol police and local police rushed to the scene and shut down traffic. The Pentagon added security and at least eight schools were placed on lockdown.

Local office workers said they kept checking the news regularly to see if there were any new developments. As they watched the news together, they were in disbelief at the horrific nature of the events that unfolded on Monday. One nearby office worker, Jennifer Shen, told Latin Post about the first reactions to the news.

"We know that security is an issue, but when it actually happened we looked at each other and asked 'Whats going on to the world?'"

However, Shen said the city and the surrounding community understand that these kinds of things can happen anytime. "Most of the people here, once we get over the initial shock . . . you just move on," she said.

President Obama took time away from his remarks about the financial crisis to address the tragedy.

"We are confronting yet another mass shooting," he said. "And today it happened on a military installation in our nation's capital. These are men and women who were going to work doing their jobs and protecting of all of us," Obama said. "They're patriots. They know the dangers of serving abroad, but today they faced the unimaginable violence that they wouldn't have expected here at home."

According to CNN, the Navy Yard is the home of the Naval District Washington headquarters, as well as a naval museum.