Who's in charge as military members enter Los Angeles? 7 On Your Side investigates

LOS ANGELES (KABC) -- The Pentagon says $134 million federal tax dollars will be paying for the National Guard and U.S. Marines to be on guard in Los Angeles. So what are they doing and how are they working with the LAPD?

"People have asked me, what are the Marines going to do when they get here? That's a good question. I have no idea," Mayor Karen Bass said during a press conference Tuesday morning. "The National Guard that are here now have one assignment and that is to protect one building, which is the federal building downtown."

And that's exactly where we have seen some of the 4,000 members of the National Guard sent to the city.

They, and their armored trucks, have fortified the federal courthouse.

General Eric Smith, who is Commander of the Marine Corps, says his men and women coming in have been given the mission to protect federal property like the courthouse and federal employees.

He says they'll be armed with shields and batons, and they will not have the power to arrest protestors.

However, some in the Senate are still concerned.

"The task that they are being assigned to do is not central to their mission as Marines," said Democratic Senator Richard Blumenthal, who questioned the General in Senate chambers this week.

"Senator, I would say all Marines are trained in crowd control," responded General Smith.

The Los Angeles Police Department says there is little coordination with the feds as they guard the courthouse, but there is communication.

Local officers say that is par for the course.

"What their (the feds) role is, is protecting federal employees and facilities. Our role is the city streets in Los Angeles," said LAPD Chief Jim McDonnell. "Certainly there is communication as it results there."

But as ICE raids continue, the chief stresses the LAPD has zero coordination with federal police on immigration arrests.