Several inmates held in a Bahrain prison were released Sunday by armed men who stormed the jail and killed a policeman, prompting a frantic manhunt. The Jau prison, south of the capital Manama, was reportedly holding Shiites involved in anti-government protests, the interior ministry reported. A statement by the ministry on Twitter said the attack “resulted in the death of policeman Abdul Salam Saif and the escape of a number of inmates convicted of terrorist crimes.” It’s unclear how many inmates are thought to have escaped. The attack is just part of an ongoing uprising against Sunni authorities by Shia-led protesters, many of whom wound up behind bars after their massive 2011 protests were crushed. Hundreds of Shia have been arrested since then, and protests continue to periodically erupt.