KARACHI, Nov 12, 2009 (AFP) - Pakistani police said they arrested seven suspected Taliban militants on Thursday accused of plotting suicide attacks in the nation's financial capital Karachi.

"We have arrested seven men and recovered four explosive-filled jackets and detonators," city police chief Waseem Ahmed told a news conference. A large quantity of explosives were also seized in the Thursday raid, he added.

"We have recovered 300 kilograms, which they planned to make into a dangerous truck bomb to target important installations and establishments of police and security forces as they have done in other parts of Pakistan."

Police in Karachi frequently claim arrests of Islamist militants.

Security services have been embarrassed by a recent spike in suicide attacks in parts of the northwest and around the capital Islamabad and authorities have denied that forces could do more to prevent attacks.

The military is pressing its most ambitious offensive to date against the Tehreek-e-Taliban Pakistan (TTP) in its South Waziristan strongholds.

"The arrested terrorists are from South Waziristan who ran away to avoid the ongoing military operation," Ahmed said.

One of the seven detainees was trained as a suicide bomber and the group's leader was an expert in manufacturing suicide jackets and training young men for suicide attacks, Ahmed said.