DACCA, Pakistan, Dec. 4— Indian MIG‐21 fighter‐bombers struck inside East Pakistan today in a series of bombing and strafing raids.

The planes hit the Tejgaon Airport in Dacca in eight raids before 1 P.M., starting at about 3 A.M. Informed sources said they destroyed the Esso refinery at the port city of Chittagong.

F‐86 Sabre jets of the Pakistani Air Force took on the MIG's in a series of spectacular dogfights watched by thousands from the roofs and streets of downtown Dacca. Air‐to‐air rockets were fired and Pakistani antiaircraft batteries filled the air with flak, visible in red tracers at night and in puffs of white smoke by day. The airport remained in use.

Claim 8 Indian Planes

It was reported that Pakistani military sources had said that eight Indian planes had been shot down in the first 10 hours of the air war. Three were reported hit by ground fire and five downed by Pakistani fighters.

The city of Dacca had not been bombed by early after noon. Thousands went about their normal activities at mid morning, after an all‐night blackout. The curfew was lifted at 7:30 A.M.

Daccans sold newspapers, sat in tea stalls and rode in rickshas and cars, paying little heed to the sporadic air‐raid sirens.

The Indian MIG's flew low enough for ground observers near the airport to see Bangla Desh symbols, green, gold, and red maps of East Pakistan, painted on the tails.

Raids Come Hourly

Their raids on the airport and the nearby military cantonment occurred hourly. In pairs, one several hundred yards behind the other, the MIG's swooped low over the airfield into a hail of anti aircraft fire.

At 12:15 one MIG, in a strafing run, was hit and burst into flames. It slowly peeled off to the west of the airfield, crashed and burst into a ball of black smoke.

One flier could be seen as he parachuted to the ground near the wreckage, in a Dacca suburb.

Reporting from the countryside on guerrilla activity and on Indian border probes was sparse, and it was not immediately known whether Indian troops had launched any ground offensive with the air raids.