Muslims regard depictions of the prophet, even favourable ones, as blasphemous.

Delwar said Facebook would be re-opened once Bangladesh had permanently blocked the offending pages.

Protests

The country's anti-crime Rapid Action Battalion (RAB) said it had arrested one man over the images of political leaders.

"A special intelligence team arrested him and he has been charged with spreading malice," Enamul Kabir, a senior RAB official, said.

"Drawing caricatures of the Prophet Mohammad is an attack on Islam and is extremely humiliating for Islam"

Hemayet Uddin, a Dhaka protest organiser

Kabir said the arrested man used at least six Facebook accounts to post the images but officials declined to give details of the depictions, which were not immediately showing up on the site on Sunday.

On Friday thousands of Bangladeshis took to the streets of the capital, Dhaka, demanding that the government ban Facebook over what they called "anti-Islamic propaganda".

The protests were triggered by a "Everybody Draw Mohammad Day" campaign on Facebook, which its anonymous promoters said was in defence of freedom of expression.

"Drawing caricatures of the Prophet Mohammad is an attack on Islam and is extremely humiliating for Islam," Hemayet Uddin, a Dhaka protest organiser, told thousands of cheering supporters.

In a counter-demonstration, Dhaka University students held a rally on the campus late on Saturday urging authorities to lift the Facebook block immediately, according to the Daily Star newspaper.

Pakistan has restored access to YouTube, but Facebook and 1,200 web pages remain blocked.

Porn allegations

Last year Bangladesh also blocked YouTube for several days after the video site hosted a recording of angry exchanges between Hasina [the prime minister] and army officers over a deadly military mutiny.

Bangladesh has nearly one million Facebook account holders - a sixth of all internet users, according to the BTRC.

Hasina and Khaleda Zia, an opposition leader, have fan pages on Facebook.

The site has previously irked the government for allegedly spreading pornography and fraudulent money-making schemes.

"There have been growing cyber-crimes related to Facebook and other social networking sites. The laws are inadequate to fight these crimes," Mohammad Sohail, an RAB spokesman, said.

In March, officers arrested a Dhaka-based stocks tipster with more than 10,000 Facebook followers on charges of manipulating Bangladesh's stock exchange.