Bahrain riot police battle protesters

MANAMA, Bahrain — Riot police in Bahrain fired tear gas and stun grenades Friday as tens of thousands of protesters staged the biggest anti-government demonstrations in weeks in the divided Persian Gulf nation.

Opposition groups called for major rallies after a prominent rights activist, Nabeel Rajab, was placed back in detention earlier this week on fresh charges linked to his social-media posts.

Bahrain has experienced near daily protests for 16 months caused by an uprising by the kingdom’s Shiite majority seeking greater political rights from the Westernbacked Sunni monarchy. At least 50 people have died in the unrest since February 2011.

There were no immediate reports of injuries from Friday’s street battles, which left piles of burning trash and clouds of stinging tear gas in the western outskirts of the capital, Manama.

Bahrain’s rulers have crucial support from neighboring Saudi Arabia but are under pressure from their U.S. allies to reopen dialogue with Shiite opposition factions. A new government initiative for talks is expected to be announced next week.