QUETTA: Pakistani police arrested 11 Iranian Revolutionary Guard officers Monday for illegally entering the country, amid tensions over a recent suicide attack that Tehran alleges was carried out by militants backed by Pakistani intelligence officials.

The 11 officers were taken into custody in Mashkel, close to the countries' border in the southwestern province of Baluchistan, police officer Dadur Raman said. He said officers were interrogating the men and had seized two vehicles.

Another security official said the guards had no travel documents.

"We need to probe that," said Murtaza Baig, a spokesman for the paramilitary border force.

Ties between Pakistan and Iran have been strained since an Oct. 18 suicide attack killed 15 members of the powerful Revolutionary Guard, including five senior commanders, and at least 27 others in the town of Pishin on the Iranian side of the border.

Iranian officials blamed the Sunni rebel group known as Jundallah, or Soldiers of God, in the attack. Iran's president and the Guard chief have since publicly accused Pakistan's intelligence service of supporting Jundallah.

Pakistan's president met with Iran's interior minister in Islamabad on Sunday to discuss the attack.

President Asif Ali Zardari vowed to cooperate in capturing any attackers and said those behind the blasts "were the enemies of both countries."

Other Pakistani officials have denied Iranian charges that the leader of Jundallah, Abdulmalik Rigi, is in Pakistan, saying he is in Afghanistan.

Pakistan has been accused of past and ongoing support of militant activities in two of its other neighboring countries, Afghanistan and India, greatly complicating relations with both of them. Tensions with another regional power would only add to the problems facing the country as it battles al-Qaida and the Taliban within its borders.

Jundullah has waged a low-level insurgency in Iran's southeast in recent years, claiming to fight on behalf of the Baluchi ethnic minority, which it says is persecuted by Iran's government.

In an attempt to boost security in the region, Iran in April put the Revolutionary Guard directly in control of the Sistan-Baluchistan Province in Iran's southeastern corner.

The Guard is Iran's strongest military force, which is directly linked to the ruling clerics. The 120,000-strong Guard also controls Iran's missile program and guards its nuclear facilities.

Iran has also accused the United States and Britain of having links with Jundullah, charges both nations deny.