Bahraini police fired tear gas at Shiite protesters on Tuesday, as they tried to reach the site of month-long anti-regime demonstrations that were brutally suppressed by the government last year.

Witnesses said hundreds of demonstrators tried to march from the village of Deih, one kilometre (0.6 miles) away, to the former Pearl Square, now razed and turned into a junction, before being confronted by police.

Police also fired stun grenades at the crowds, who gathered to pray before beginning their demonstration, according to witnesses.

The interior ministry said on its Twitter page that police confronted a "group of vandals" on the Budaiya artery, after they "blocked the road, hurled petrol bombs, and terrified passers-by".

Demonstrations have shaken Bahrain since it crushed a Shiite-led uprising against the ruling Sunni regime in March last year.

The kingdom came under strong criticism from international rights groups over the deadly crackdown.

Bahrain, home to the US Fifth Fleet and strategically situated across the Gulf from Shiite Iran, has continued to see sporadic demonstrations, though mostly outside Manama.

According to the International Federation for Human Rights, a total of 80 people have been killed in Bahrain since the violence began on February 14, 2011.

The United States last week expressed concern about rising violence in Bahrain, one year after an inquiry report was issued on the violence, saying the country needed to put more of its recommendations into effect.