England have refused to play a Test in the volatile southern port city of Karachi on their tour of Pakistan later this year citing security concerns for their players.

"The blasts in London prove that no city is safe today from terrorist activities but life has to go on, as it is going on in London. So why discriminate against Karachi?" Miandad asked.

Karachi, long plagued by violence between rival ethnic and sectarian gangs, has been hit by a spate of militant attacks including bomb blasts and shootings since the September 11, 2001, attacks on the United States.

More than 50 people were killed in four blasts on London's transport network on Thursday.