President Obama on Monday expressed sympathy for the victims of the shooting at the Washington Navy Yard in Southeast Washington and said he wants authorities to work together to determine what happened.

"I’ve been briefed by my team on the situation," Obama said. "We still don’t know all the facts, but we do know that several people have been shot, and some have been killed. So we are confronting yet another mass shooting. And today it happened on a military installation in our nation’s capital. It’s a shooting that targeted our military and civilian personnel."

The shootings are the second time a military installation has been targeted during Obama's presidency. In the 2009 shootings at Fort Hood in Texas, when Army Maj. Nidal Hasan killed 13 people in a gun rampage.

Obama expressed sympathy for the victims and those close to them. He called the shootings a "tragedy."

"They know the dangers of serving abroad, but today they faced the unimaginable violence that they wouldn’t have expected here at home," he said.

Obama was speaking on the fifth anniversary of the 2008 economic collapse about the progress being made in the economic recovery.

Multiple people have been killed, and authorities said shortly before Obama's speech that as many as two shooters remain on the loose. They said one shooter has been killed.

For more on the latest in the Navy Yard shootings, visit the Post's live blog.