Islamabad, June 6 (Reuters): Pakistani police foiled planned suicide attacks on the twin cities of Islamabad and Rawalpindi, arresting six suspects and seizing three vehicles packed with explosives, officials said today.

The arrests came days after the al Qaida carried out a suicide car bomb attack on the Danish embassy in Islamabad on Monday that killed six people, all of them Pakistani. The arrests were made late yesterday in the garrison town of Rawalpindi, the city neighbouring the capital. “We have arrested suspected suicide bombers,” said Rao Iqbal, Rawalpindi police chief.

He said police had also seized three vehicles laden with a large quantity of explosives from Dhok Kala Khan, one of the city’s congested neighbourhoods.

The arrests triggered a high alert in the two cities.

Security was tightest along Islamabad’s Constitution Avenue, the duel carriageway leading to the presidency building, National Assembly, supreme court, various ministries and the diplomatic enclave where many embassies are located.

Concrete barriers were placed across the broad avenue, and regular entry points to the enclave were closed, while razor wire was laid around the perimetre of key buildings.

The Danish mission, which had been under threat ever since the publication of cartoons of the Prophet Mohammed by Danish newspapers in 2005, was located in a plush residential neighbourhood.

A Danish team has arrived in Pakistan to work with agents investigating the attack on its embassy.

A senior Pakistani official of a joint investigation team said several people had been picked up, but none had been linked to the attack so far. Police were also preparing a sketch of the suspected bomber.

Foreign envoys met yesterday with Rehman Malik, the adviser to the Prime Minister on the interior, and he told them that Islamabad police were being reinforced with paramilitary troops.

Malik assured those ambassadors whose embassies were located outside the diplomatic enclave that he would take up issues regarding the provision of land for them to relocate.