Two attacks outside the Bahraini capital Manama killed one policeman and wounded five, the interior ministry and police said on Sunday, in the latest unrest to rock the Sunni-ruled Shiite-majority Gulf state.
A bomb killed one policeman and wounded two in a Shiite village near Manama, Bahrain's head of public security said.
"Terrorist groups targeted a police station in Sitra" late on Saturday, general Tariq Hasan said in the statement carried by the official BNA news agency.
"As police attempted to secure the area... the terrorists blew up an improvised bomb against security forces in an attack that killed policeman Yasser Dhaib and wounded two others."
In Janabiya, another Shiite village outside the capital, a "group of terrorists attacked a security patrol with Molotov cocktails," the interior ministry said on Twitter.
"The patrol was burnt and three policemen were injured," it added.
Bahraini authorities often use the term "terrorists" to refer to Shiite demonstrators who have kept up pro-democracy protests despite a 2011 crackdown backed by Saudi-led Gulf troops, sparking repeated clashes with security forces.
In mid-February, a police officer was killed by a petrol bomb during clashes with protesters, after a teenager was shot dead during a demonstration marking the second anniversary of the launch of the protests.
The police station in Sitra has been the scene of frequent clashes.
Earlier this month, a Bahraini court sentenced seven Shiite men to 15 years in prison after convicting them of attempted murder over the wounding of a police officer in Sitra in August 2012.
The group were also convicted of setting the police station ablaze with petrol bombs and of taking part in an "unauthorised gathering."
In May, 31 people were jailed for 15 years after they were convicted of attacking a police patrol in Sitra.
At least 80 people have been killed in Bahrain since Shiite-led pro-democracy protests erupted in February 2011, according to the International Federation for Human Rights.
Strategically located across the Gulf from Shiite Iran, Bahrain is home to the US Navy's Fifth Fleet and is an offshore financial and services centre for its oil-rich Gulf Arab neighbours.