Bahrain says it will expand security before hosting next week's Formula One race after a series of explosions, including a gas cylinder blast that set a car ablaze in the Gulf nation's financial district.

The attacks caused no injuries and limited damage, but sent a message that anti-government militants could step up violence before Sunday's F1, the premier international event in the kingdom.

Bahrain has been wracked by more than two years of unrest between the Sunni-led government and majority Shiites seeking a greater political voice.

Bahrain's Interior Ministry says the four blasts happened in quick succession late Sunday, ending with the gas canister explosion inside a stolen car in Bahrain's Financial Harbor.

Bahrain says it will provide "adequate" security to protect fans and F1 teams.