A civil lawsuit has been launched over alleged "indiscriminate" arrests of lawyers, legal observers, journalists and medics amid protests that turned violent in Washington DC during President Donald Trump's inauguration ceremony last week.

Jeffrey Light, an attorney who filed the lawsuit on Friday - the same day that the inauguration was held - against police officials, told Al Jazeera that about six journalists, more than three lawyers and a number of medics were among more than 230 who are facing rioting charges.

Rioting carries a maximum penalty of 10 years in prison and $25,000 fine.

At least three of the lawyers detained had been marked as legal observers - who are designated to protect the rights of activists at demonstrations, Light said.

Light, who has been contacted by many of those arrested, accused officers of using "excessive force" after some protesters hurled rocks and bottles at police, who responded with volleys of tear gas, stun grenades and an "indiscriminate" mass arrest.

Anti-Trump protests spring up across the US

During the demonstration, at least one car was set on fire and windows of some downtown businesses were damaged by protesters.

"Everybody has been charged with felony rioting and they [the police] have not given a reason. They arrested everyone in a particular area. Police have reported that unspecified people threw objects, but have not accused specific individuals of throwing objects," Light said.

"It is unconstitutional because people were arrested without any determination by police that they were doing something wrong."

The DC Police Department's press office told Al Jazeera that they can not comment on the arrests due to the lawsuit.

Interim Police Chief Peter Newsham, who has been named as a defendant in the lawsuit, has been quoted by local media as saying that it was "disappointing" that the clashes and arrests happened, but was "very, very pleased" at how his department handled the situation.

READ MORE: Environment agency faces 'media blackout' under Trump

US protests to protect civil rights

Light's comments to Al Jazeera on Wednesday came as the Committee to Protect Journalists (CPJ), a US-based media watchdog, issued a statement calling on DC authorities to drop rioting charges against the detained journalists.

Evan Engel, a senior producer at the news website Vocativ, Aaron Cantu, a freelance journalist who has written for Al Jazeera and Truthout besides other news agencies, and Alex Rubinstein, a reporter for Russia-based TV network RT, were among the media members detained.

Carlos Lauria, of the CPJ, told Al Jazeera that the "excessive" charges against the journalists have raised fears of press freedom being under threat in the country.

"Journalists should be able to cover the inauguration without interference, especially because people have the right to recieve information about what is going on that important day ... The crackdown sends a chilling message to reporters and the media who cover protests," he said.