BEIJING, April 27 (Xinhuanet) -- Eleven people have been killed and 40 injured in a bomb blast outside the office of one of ’s main political parties in Karachi. Four children were among those killed in Friday' attack.

Authorities said the bomb had been planted on a motorbike and placed outside the office of the Awami National Party. With general elections in Pakistan next month, militant groups have stepped up their attacks on political parties contesting the elections.

On Thursday, the office of the Muttahida Quami Movement or the MQM in Karachi was the target of Taliban militant attacks.

The increasing number of attacks on liberal and secular parties contesting the May elections has led to many changing their campaign strategy and raised questions of whether the vote can be considered valid if some mainstream parties cannot properly take part.

(Source: CNTV.cn)