Updated

A defense lawyer in Bahrain says a prominent human rights activist is in custody after defying an official ban on protest gatherings in the Gulf kingdom.

The detention of Yousef al-Muhafedha could further embolden Shiite-led demonstrators seeking a greater political voice in the Sunni-ruled nation, which is home to the U.S. Navy's 5th Fleet.

Lawyer Mohammed al-Jishi says authorities Saturday decided to keep al-Muhafedha in custody for at least week while prosecutors study possible charges.

Al-Muhafedha, detained late Friday, has led the Bahrain Center for Human Rights its head, Nabeel Rajab, was arrested earlier this year and is appealing a three-year sentence for allegedly encouraging protests in the nearly 21-month-old uprising.

Bahrain's decision last month to outlaw protests has brought sharp criticism from rights groups and allies including the U.S.