A suicide attack in Pakistan's restive tribal region killed two soldiers and injured four.
Troops averted another attempt, gunning down a suspected bomber.
In another attack, militants destroyed two police check posts in the North Waziristan tribal region.
The attacks are seen as a response to the crackdown on Islamabad's radical Lal Masjid.
A suicide bomber struck a joint check post of the army and paramilitary force in Mir Ali town killing two soldiers, defence spokesman Major General Waheed Arshad said.
The four injured soldiers are stated to be in critical condition, according to media reports.
The security forces blocked the main road between Miranshah and Bannu, a major city at the edge of North Waziristan.
Reports from Malakand said troops shot dead a suspected suicide bomber scaling the wall of a heavily fortified police station in Matta near Swad.
The youth reportedly was shot as he continued to climb the wall despite warnings from security personnel manning the bunkers.
Also, unidentified men blew up two security check posts in North Waziristan after the local Taliban leadership called for attacks on the army.
The attacks came two days after militants in North Waziristan region scrapped a peace agreement with government amid weekend suicide bombings that killed more than 70 people across North West Frontier Province, most of them policemen and soldiers.
Local Taliban commanders had asked their men to launch guerrilla attacks on Pakistani security forces.
Meanwhile, President Pervez Musharraf, who presided over a high-level meeting at Rawalpindi, decided that the deployment of security forces in NWFP and Fata be enhanced.
He reviewed the law and order situation in NWFP and Fata, where a number of security personnel and civilians were killed in the weekend terrorist attacks, in the meeting attended by Prime Minister Shaukat Aziz and top military officials.
Musharraf said the Waziristan accord -- that was ended by the militants on Sunday -- was not signed with Taliban, but with tribal notables.
He directed NWFP Governor Ali Jan Muhammad Orakzai to hold meetings with tribal leaders.