Story highlights Kokesh is arrested on 2 charges, 1 of which is a weapons charge

He is placed in custody in northern Virginia, police say

Kokesh has a long history of speaking out, including recent YouTube video

He used Facebook to call for an armed march in Washington

Iraq veteran turned pro-gun activist Adam Kokesh was arrested on two charges, including having a gun while in possession of an illicit drug, police said Wednesday.

His arrest comes after authorities late Tuesday searched the suburban Washington home of Kokesh, who recently made headlines with his July Fourth video posted to YouTube in which he loaded a shotgun in the middle of the national capital's Freedom Plaza.

He also used Facebook to call for an armed march in Washington for the same day but called off the event in May. It is illegal to carry firearms in the District of Columbia.

Kokesh spent Tuesday night into Wednesday at Fairfax County Adult Detention Center in northern Virginia, U.S. Park Police spokeswoman Pamela Smith told CNN. He was still there as of Wednesday afternoon.

He faces two charges -- illegal possession of a schedule I or II drug and having a firearm while in possession of such a drug -- Smith said. Under Virginia law, schedule I drugs such as heroin and LSD have a high potential for abuse and no accepted medical use, and schedule II drugs such as PCP, cocaine and methamphetamine are addictive, have a high potential for abuse but have accepted medical uses.

Smith earlier told CNN that authorities had executed a search warrant on Kokesh's home in Herndon, Virginia, which is about 20 miles west of Washington.

"It is still an ongoing investigation," Smith said then.

She declined to comment on what, if any, weapons had been discovered in the search.

Kokesh has a long history of speaking out. He was discharged from the Marines in 2007 for wearing his uniform during an anti-war protest.

In his now infamous YouTube video, Kokesh states: "We will not be silent. We will not obey. We will not allow our government to destroy our humanity."

Then, loading shells into the shotgun, he looks into a camera saying, "We are the final American revolution. See you next Independence Day."