MAHDEYA, Egypt -- Shadi Meneayi left his hometown in North Sinai more than eight months ago to help lead a campaign of terrorist attacks against Egypt's new military-led government, his relatives say.
His hometown, a sprawling collection of hundreds of cinder-block homes that was long known as a hub of such Islamist militancy, has paid a heavy price.
In its 8-month-old battle to crush the militants, the military has bombed and destroyed Mr. Meneayi's former home, then his family's house down the hill, a new home his brothers were building to replace it and a hut they constructed as interim shelter. Half the homes nearby, several dozen in all, have been reduced to rubble, and local people tell stories of children fleeing into the desert or being wounded by shrapnel as warplanes and helicopters swooped down.
The wreckage of similar towns across the North Sinai, many with a far less certain connection to extremism, tells the story of a crackdown so sweeping that even ardent supporters of the military say it risks spreading sympathy for the militants it is hunting.
"The military is killing innocent civilians, not fighting armed terrorists," said Abdel Aziz Yousef, 21, whose brother, Mohamed, 31, was killed in broad daylight this month by a nervous soldier at a checkpoint, his family and friends say.
Both brothers and their family had at first cheered the military for taking on the extremists. But "if you want to liberate Sinai from terrorism, don't take the good ones with the bad ones," Mr. Yousef said, because each innocent you kill "will create 50 terrorists."
The Bedouin residents of Sinai, the desert peninsula bordering Israel, have long complained of neglect. They refer to the mainland as another country, "Egypt." And they say that the Egyptian police have always applied abusive tactics like arbitrary or mass arrests, treating any Bedouin as a suspected criminal.
But after the security forces crushed the earlier Islamist insurgency that flared in southern Egypt in the 1990s, Islamist militants began to find a haven here.
The peninsula exploded in violence when the military overthrew President Mohammed Morsi of the Muslim Brotherhood last summer, and it is now the center of an extremist campaign of bombings and assassinations targeting the military and the police.
The security forces -- this time led by the army, instead of the police -- have responded with a crackdown on a scale that residents and historians say Sinai has never seen. But although the anti-government violence has spread, Sinai remains its wellspring and a pivotal test for the authorities.
Military officials say they are as cautious as possible about the safety of their troops and innocent civilians. "But the terrorists are hiding among the people, and you don't know who is who sometimes," said one senior military official, speaking on the condition of anonymity because he was not authorized to discuss the operations. "That is why they should notify the police if they have terrorists among them, and expel the terrorists."
But even residents who support the military takeover complain that they feel caught in the crossfire. Mahdeya is only one of several North Sinai villages where dozens of homes have been destroyed by air raids or artillery. To prevent militants from detonating bombs with mobile phones, residents say, the military cuts off all mobile and almost all landline telephone service for most of each day, making it impossible for residents to call ambulances or other emergency assistance.
In the provincial capital, Arish, near the hot zone of militant activity, administrative buildings are blocked off by a ring of sand berms, concrete blocks and barbed wire that protect the military, police and intelligence headquarters inside. Residents murmur fearfully of a command center there called Brigade 101 that is rumored to be a center of harsh interrogations. "A slaughterhouse," several called it.
"The people who get taken to Brigade 101 don't get out," said one doctor at the local hospital. Spokesmen for the military and the government did not answer messages or declined to comment.
The government publicly blames the Brotherhood, the Islamist group linked to Mr. Morsi, for the violence. But residents said that the security forces treated Sinai towns known as Brotherhood strongholds differently.
In Beer al-Abd, a Brotherhood center, there are few checkpoints and no communications blackouts. Unlike in the more militant areas, soldiers and the police can be seen moving easily in the streets without fear of attack.
Instead of military operations, soldiers and policemen make predawn raids on Brotherhood homes. A local leader who identified himself as a Morsi supporter said he had not spent a night at home since August for fear of arrest.
"I see my wife and children in morning sometimes," he said.
Residents of the more violent areas said revenge sometimes played a role as well as ideology. Two young men described a cycle that began in September 2012 when a sheik from their tribe, Khalaf Meneayi, criticized the local extremists.
To try to avoid a blood feud between families, the extremists sent one of the sheik's own relatives to assassinate him. The killing nonetheless set off an exchange of retaliatory attacks between the family and the extremists. So after the military takeover in Cairo, the two young men became informers for a military unit, in part to exact more revenge against the extremists.
Then an officer in another military unit shot one of the informers in the leg, he said, displaying his shattered leg to a visiting journalist. So now they, too, have soured on the army.
When the military officers call for information, "I say, 'I don't know of any news,' " one of the two men said. "Even if I see the terrorists in front of me, I will say, 'It doesn't concern me.' "