The US is "very concerned" with violence exhibited in Bahrain during protests this week in the Persian Gulf nation, Reuters reported US State Department spokesman P.J. Crowley as saying on Tuesday.
Crowley called on both protesters and government forces "to exercise restraint and refrain from violence."
Two protesters have been killed in two days of demonstrations, prompting Bahrain's King Hamad bin Isa Al Khalifa to promise reforms and investigate the deaths.
"The United States welcomes the government of Bahrain's statements that it will investigate these deaths, and that it will take legal action against any unjustified use of force by Bahraini security forces," Crowley said.