Zlitan, Libya (CNN) -- A grown man sobbed as friends led him out of the mosque. Mustafa Naji al-Mrabet's left hand and feet were bandaged, there were bloodstains on his robes, and the valve for an intravenous needle still stuck out of his arm. He was both a husband and a father, deep in mourning.
Nearby, his brother-in-law, 26-year-old Abubakr Ali cried like a child. Ali pulled back the blankets covering two small coffins. Inside lay the bloody bodies of his nephews, Mohamed and Motez al-Mrabet, ages 5 and 3. Their mother Ibtisam lay in a coffin beside them.
All three were killed early Thursday morning as they slept, neighbors and relatives said, when their house on the outskirts of this coastal city was hit by a NATO airstrike. Family members said a third child, 8-year old Naji, was in intensive care after suffering serious injuries.
Officials from Moammar Gadhafi's embattled government brought journalists to the ruins of al-Mrabet family's 2-story villa in a residential neighborhood on Thursday.
"In all my 36 years I've never seen a day like this," said a neighbor named Salah Buharto. He said the 6:30 a.m. blast was so powerful, he initially thought his own house had been hit.
When asked about the suspected air strike, a NATO spokesman told CNN: "NATO made a strike in Zlitan at 6:30 a.m. (Thursday) local time. The target was a command and control facility held by government forces.
"We have had no reason to believe that there were any civilian casualties," said another NATO spokesman to CNN, also speaking on condition of anonymity. "But we take these reports very seriously and we are looking into the matter. We have a process that we go through."
For weeks, Zlitan has been the target of an intense NATO bombing campaign. The number of buildings and compounds devastated by air strikes have visibly increased since foreign journalists were taken on a government-controlled tour of the small city last month.
The Gadhafi regime accuses NATO of hitting food warehouses, health clinics and schools. But a tour of one bomb site on Thursday revealed evidence suggesting the target was not entirely civilian.
At the compound of a bombed-out law school where classroom walls were scorched and broken glass littered the floor, CNN found several military uniforms lying on the ground next to wooden ammunition crates. When asked about the military paraphernalia, a government escort said the ammo boxes and uniforms "belonged to school security guards."
Meanwhile, every few seconds, rocket and cannon fire rumbled in the distance, as rebels and regime loyalists fought a deadly artillery duel across the front lines a few miles to the east of the city. Zlitan is located less than 50 miles west of the rebel-held port city of Misrata, which survived a long, bloody siege by Gadhafi forces.
Over the last week, rebel commanders claimed to have captured parts of Zlitan after advancing west from Misrata. But on Thursday, the city center appeared to remain firmly in loyalist hands.
The combined NATO and rebel offensive have clearly taken their toll on Zlitan. On Thursday, the city's streets were mostly deserted and most of the shops were closed. Residents said they suffered from long power outages lasting 10 hours or longer. Civilian cars and an ambulance smeared with dirt -- a tactic used by both rebels and regime fighters to camouflage vehicles -- raced through the town center.
The rebel Transitional National Council and its allies in Washington, London, and Paris have long demanded that Gadhafi step down. But more than five months after anti-Gadhafi protests first erupted across Libya, the flamboyant colonel is still clinging to power. His government is threatening a war of attrition against his enemies.
"This war, this honorable confrontation, could go on for years," warned Gadhafi's main spokesman, Musa Ibrahim, in a press conference on Wednesday. "We do not want it to...but from the beginning we were preparing ourselves to fight on the diplomatic front for years, on the military front for years, on the economic front for years."
As always in conflict, civilians pay the highest price.
At Thursday's funeral, Abubakr Ali watched volunteers carefully bury the bodies of his sister and two nephews next to the neighborhood mosque.
"This was a civilian home. No army, no military, no Gadhafi forces. It's a family sleeping safely in their place," he said. "This is the protection of civilians," Ali added with disgust. He was referring to the United Nations Security Council resolution which authorizes the use of force in Libya in order to protect civilian lives.
As tears streamed down his face, Ali took a Kalashnikov rifle and fired a round of bullets into the air.
"Screw NATO and the (rebel) rats and screw those who gave the coordinates for the attack," he yelled. "God damn you now and in the afterlife. Moammar (Gadhafi), I'm with you until the last drop of blood."