Updated

Journalists and their supporters are joining an international protest against the detention of four Al Jazeera staffers in Egypt.

Media workers and free speech advocates with masking tape stuck across their mouths gathered in places including London's Trafalgar Square, Lebanon's Martyrs' Square and in Kenya's capital, Nairobi.

On the Internet, journalists posted photographs of packed newsrooms bearing signs saying "Journalism is not a crime."

Peter Greste, Mohammed Fahmy, Baher Mohamed, and Abdullah Al Shamy, are among 20 defendants being tried on charges of belonging to and aiding a terrorist organization for their coverage of the Muslim Brotherhood.

They have pleaded not guilty. Al Jazeera says the reporters were merely doing their jobs.

The Associated Press is one of dozens of media organizations which have called on Egyptian authorities to release the reporters.