Singer Adam Lambert has tweeted that he's “shocked” at the arrest of gay activist Lt. Dan Choi.

“So shocked that this happened today at the same hour and same city as I was performing in,” Lambert messaged along with a link to gay glossy The Advocate's coverage of the arrest to his more than 1 million followers on Saturday.

Americans Choi and Andy Thayer and France's Louis-Georges Tin were among the 18 gay activists arrested Saturday attempting to hold a Gay Pride parade in Moscow. Police also arrested 14 opponents.

Choi is best known for protesting “Don't Ask, Don't Tell,” the 1993 law that bars gay and bisexual troops from serving openly.

He was booted from the Army under the policy for acknowledging he's gay on MSNBC's The Rachel Maddow Show.

“I am here in Russia in solidarity with our brothers and sisters who are fighting for the basic right to express their identity,” Choi said in a video before his arrest.

In a video taken with his cell phone from inside a Russian paddywagon and uploaded to YouTube, Choi said he had suffered a “slight injury to my right ear” during the arrest and was experiencing “massive ringing.”