The king and queen of Thailand escaped unhurt today when two pipe bombs exploded at an awards ceremony in the country's southern-most province, injuring a number of people, the government announced.

Sources within the government put the number of wounded at more than 40, of whom a dozen or so were reported to have been hurt seriously. The royal couple and their children continued the ceremony after the injured were removed.

There was no immediate indication who was responsible for the incident or whether the aim had been to assassinate the king, but Yala Province, where it occurred - nearly 500 miles south of here - is a hotbed of Moslem separatism.

Some observers here speculated that the intent had been to dramatize the separatist cause rather than to harm the king, who enjoys high regard for his visible and active demonstrations of conern for the underprivileged.

A government statement expressed a similar view, saying: "Whoever did this intended to cause damage and to have his action publicized abroad."

Today's ceremony was one of a series of visits the American-born King Bhumibol Adulyadej and Queen Sirikit have been making around the country, presenting land, medical supplies and other tangible symbols of concern for the people.

Tuesday the king celebrated his 10,000th day on the throne. Under Thailand's constitutional monarchy, the king exercises little direct powers as head of state and stays aloof from politics. Raher, he serves as a symbol of national unity and identity and is revered as a demigod.

Since taking the throne in 1950, at the age of 23, Bhumibod has been perhaps the most active king in the country's history, spending a great deal of his time away from the capital. In addition, the Western-educated monarch is a talented jazz musician and has written a number of his own compositions.

Still, the government stepped up security after today's incident, which came against a backdrop of tension and rumor here in the capital. The annual promotion list for the military is about to be published, and Bangkok is filled with the rumor that there will be a coup attempt any day.

The coup that established the current government, headed by premier Thanin Kraivichien, a former Supreme Court justice, occurred Oct. 6 last year. The legislature - which had managed to pass only two bills in the five months preceding the coup - has remained suspended since then.

The separatist sentiment in the Moslem, ethnically Malay southern part of the country is a long-standing problem for the government in Bangkok, and it has sought assistance from neighboring Malaysia in combating it.

Malaysia, in turn, has asked Bangkok for help in fighting the guerrillas of the Communist Party of Malaya, who make cross-border raids from bases in Thailand.