Updated

Two senior Egyptian police officers were killed Thursday by land mines possibly rigged to explode during a search of the Sinai Peninsula's (search) rugged mountains for terror suspects linked to recent tourist resort bombings, security officials said.

Maj. Gen.Mahmoud Adel (search) and Lt. Col. Omar Abdel Moneim (search) were the highest-ranking police officers killed in Egypt since an Islamist insurgency in the mid-1990s, and the first slain since 4,000 security personnel began a sweep Sunday of the northern Sinai for suspects linked to July's Sharm el-Sheik (search) attacks and two October resort bombings.

Thursday's blasts by two land mines occurred on 5,900-foot Halal (search) mountain, some 37 miles south of the Mediterranean coastal town of el-Arish (search), the Interior Ministry said.

It did not say if the mines had been planted by suspected militants or left over from previous Arab-Israeli wars.

But at least two security officials said initial investigations indicated that fugitives hiding on the mountain had concealed the mines. The officials spoke on condition of anonymity because they were not authorized to release the information.

The first mine exploded as a bulldozer was clearing a path for two vehicles carrying Adel, Moneim and several other security personnel, said the officials. The second detonated after the officers got out of their vehicle to inspect the scene of the first blast.

The Interior Ministry said another two officers were wounded, and the security officials said the civilian bulldozer driver was also injured.

After the explosions, security forces found three pickup trucks loaded with drugs and weapons in the area and arrested five people. Officials are still trying to determine the identities of the five.

The killings were the first of Egyptian security officers in Sinai since a driver shot a policeman to death in May. In February, another police officer was killed during clashes with suspected militants connected to the Taba and Ras Shitan bombings.

Police have been scouring northern Sinai's deserts and jagged mountains and storming suspected militant strongholds for those behind the July 23 Sharm el-Sheik bombings that killed at least 64 people and the October attacks. At least 650 people have been detained since Sunday.

A key suspect thought to be among those at large is Salem Khadr el-Shenoub, who is believed to have harbored militants linked to the Taba and Ras Shitan attacks.

El-Shenoub has allegedly booby-trapped caves and valleys on and around Halal Mountain, some 37 miles south of the Mediterranean coastal town of el-Arish, said an official who spoke on condition of anonymity because he was not authorized to release the information to the media.

Many of Sinai's rugged mountains have been traditional safe havens for criminals and fugitives involved in smuggling, drug running and other illegal activities.

During the ongoing police hunt for suspected militants, the area's native Bedouin tribesmen — with their knowledge of smuggling routes and hideouts — have emerged both as key to search efforts and as suspects themselves.

With several terror suspects hailing from northern and central Sinai, some believe the area may have become a breeding ground for extremists.

But Dia'a Rashwan, an expert on Islamic groups, rejected the theory that criminals living in the mountains were cooperating with militants, as the two groups had different ideologies and interests. He said, however, that they might make exceptions and harbor militants if they have family ties.