Police in Dhaka arrested eight Islamists after they attacked a sculpture depicting a group of white storks, in a continuing campaign against statues and artwork they say are forbidden by Islam.

"We detained eight members of a fanatic Islamist group for damaging the sculptures at Dhaka's Motijheel commercial area around midnight on Saturday," police officer Fazlul Haq told Reuters on Sunday.

Witnesses said nearly 400 Ulama Anjumane Al Baiyanat activists gathered around the sculptures with shovels and hammers, chanting slogans calling for the demolition of all stoneworks, which some hardliners consider to be idols.

Clash with police

First they tried to pull down the 13-metre high sculptures by putting ropes around the necks of the storks. Unable to do this, the group attacked the base with hammers and other tools, the witnesses told reporters, before clashing with police trying to disperse them.

Various Islamist groups, including the Al Baiyanat, have been vandalising sculptures in Muslim-majority Bangladesh in recent months.

They destroyed a huge statue of mystic poet Lalon Shah outside the Dhaka international airport in October, triggering a national protest.

"These are attacks on Bengali culture and a state of impunity has encouraged them to carry out such acts," said Mrinal Haque, who sculpted both Lalon and the storks.