"NATO belongs to murderers, Istanbul belongs to us," chanted the protestors from a self-styled anarchist group calling itself Anarsistanbul as they gathered in the downtown Beyoglu district in the city's European quarter.

All the demonstrators were wearing masks depicting alien faces made of green and blue plastic.

"We are wearing the masks, but we suspect those who do not oppose NATO are actually aliens," said a spokesman for the group.

Police told protestors they had two minutes to take off their masks and a protestor reponded by saying the police had five minutes to disperse, Anatolia said.

Officers then arrested the demonstrators.

There are almost daily protests in Turkey against the NATO summit to take place in Istanbul on June 28-29 which will be attended by US President George W. Bush among other Western leaders.

WAR.WIRE