Most of Iran's petroleum workers have ended their strike and crude oil production is picking up, National Iranian Oil Co. sources said yesterday.

Nevertheless, exports of the country's chief sources of income, usually accounting for more than $20 billion a year, remained well below normal levels, partly because of rough weather in the Persian Gulf, the sources said.

The return of more workers to their jobs came as a shooting incident raised tensions at the Tehran bazaar, which remained on strike in another antigovernment protest. Reported outbreaks of violence have been limited since the military government took over last week.

Independent confirmation that the oilfield strike is ending were unavailable because the plants are under heavy military guard and are off-limits to unauthrized persons. In the current atmosphere of distrust of the government, there was speculation that the return to work was proceeding much more slowly and the government reports were an attempt to create a snowballing effect.

A company spokesman said about 80 percent of the oil workers went back to their jobs, but it is still unclear whehter they are all actually performing their duties or continuing a workslowdown that has been staged by some refinery employes.

In any case, he said, oil production crept upward to 3.3 million barrels yesterday, still well below the year's average of more than 5 million barrels a day ubut up by nearly a million barrles a day from Monday's figure.

The level of exports was not revealed, but industry sources said it was being held down by roygh guld waters that make it difficult for tankers to berth. Of the amounts produced yesterday, some 2.5 million barrles are available for export after normal domestic uses are met.

Company officials said Iranian employes of the Abadan refinery, one of the worlds largest, have ended their three week old strike along with workers at the Khang Island tanker loading terminal and the Gachsaran oil fields. But they said workers at the Tehran refinery and the Ahwaz and Aghapair oil fields are still on strike.

According to reports from the southwestern oil prodcuing region, the strike at Abadan refinery, where some of the most militant oil workers are employed, fell apart after military authorities arrested 18 leaders, including members of the 12-man "coordinating committee," and moved troops into the plant.

Meanwhile, according to witnesses, yesterday's Theran violence began when youths threw firecrackers under army trucks stationed on a street bordering the bazaar, which traditionally has been a bothed of religious and political opposition to Shah Mohammad Reza Pahlavi. The witnesses said troops responded by firing rifle shots and bursts of automatic weapons mostly into the air but sometimes at people. At least two bodeis were seen lying in pools of blood on the street after the incident.

Other accounts said bazaar merchants tried to stage a demonstration starting from another part of the market place, but they awere dispersed by army firing, which went on sporadically in the area for nearly three hours.

Troops sealed off a street on the west side of the huge bazaar and mounted a machine gun in the second floor window of a building facing the covered market's main entrance. Fifteen trucks and jeeps filled with soldiers guarded the entrance after the shooting as passersby gave them sullen stares.

Inside the rabbit warren of alleys, catwalks, courtyards and passageways, shops were still covered an black flags still hung to protest the shooting of student demonstrators 10 days ago and the subsequent installation of a military government.

The oil workers have been striking in part for political demands, notably for an end to the martial law imposed Sept. 8 for six months.

But the government has been unwilling to give in to this and other political demands - including explusion of foreign oil workers - as it did to earlier calls for higher pay.

In another example of growing anti-Western sentiment among the strikers, angry Iranians in the oil center of Ahwaz stoned the car of George Link, the American managing director of the Oil Services Co. of Iran. Link was reported unhurt, but his driver was injured. The company runs the oil fields of the main producing area of Khurestan Province under a service contract with the National Iranian Oil Co.

Yet, one company official said. "The situation is getting better and the prospects for ending the strikes entirely are much brighter." He cited "the gradual return to work."

In Tehran, an employe of a U.S. company, American Bell International, said he and 200-to-300 colleagues stayed away from their jobs at the Telecommunications Company of Iran today after Iranian workers forced them out of their ofifces Monday to back demands for the dismissal of all foreign telecommunications personnel. There was no sign of any steelement of the dispute.

[Meanwhile the official Pars news agency said that three people were killed and 19 injured in Sonqor by government troops when a group of protesters set fire to the offices and home of the provincial governor, Associated Press reported.]

Employees of the major Iranian newspapers, which were closed when the military government came to power, remained on strike over attempts by the new military authorities to reimpose press censorship, which was lifted by the previous civilian Cabinet.

At two English-language newspapers, printers have reportedly refused to put out a censored paper.Several Iranian journalists are under arrest, and others are on the strike in protest.

The government also appeared to be cracking down on broadcasting by the Persian service of the BBC, which has conveyed news to Iranians in their local language. Authorities have tried to suppress the broadcasts in the past. A member of Parliament complained in London that the military authorities are jamming the BBC's Persian service, and that the organization's correspondent in Tehran has received formal warnings from the government against reporting opposition views.