The Rhodesian military command said today that Patriotic Front guerrillas had committed numerous violations during the first day of the cease-fire but British officials monitoring it indicated the general situation was peaceful.

According to the Rhodesian military statement, more than 700 guerrillas crossed into the embattled British colony, mostly from Mozambique, despite a ban on cross-border movement since an agreement ending the seven-year civil war was signed in London eight days ago.

The Rhodesian command said a convoy of its security forces was attacked by guerrillas this morning, almost nine hours after the truce took effect The military said its forces "reacted in self-defense," as they did later when a farm was attacked. There were no reports of casualties in any of the incidents.

A co-leader of the Patriot Front guerrillas, Robert Mugabe, said in Maputo, Mozambique, that he "informed the British government that things might not move as smoothly as we had hoped."

Special correspondent Martha Honey, who interviewed Mugabe, reported that he is now expected to arrive in Rhodesia within a week or two.The accelerated plan for the return of the long-exiled leader is a consequence of the death on Wednesday of his military chief, Josiah Tongonara.

Mugabe discounted the possibilty that guerrillas in the Rhodesia bush, thinking Tongongara was murdered, might violate the cease-fire. "We will tell them the truth," that he died in an auto accident, Mugabe said. Other guerrillas in the Mozambican capital said a reason for Mugabe to move earlier to Salisbury would be to reassure the guerrillas, Honey reported.

Elections are scheduled for the end of February but an aide to Mugabe said a planned strategy meeting with Patriotic Front co-chairman Joshua Nkomo has been called off. Indications so far are that the two will contest separately, against former Prime Minister Abel Muzorewa.

The alleged cross-border movement was potentially the most serious threat to the tenuous cease-fire. It was reported to have come from Zambia as well as Mozambique. Britain has asked both countries, supporters of the Patriotic Front, to cooperate in stoping guerrilla infiltration.

British spokesman Nicholas Fenn said he could not confirm the reports of guerrilla movements and added that the colonial government would issue its own communique on Sunday. He downplayed the shooting incidents, saying they were not necessarily breaches of the cease-fire. "It could be hooligans," he maintained.

Fenn made clear that the British administration which has taken over temporary control of the country pending the elections, was not happy with the Rhodesian military announcement. "We would not have put it in those terms," he said.

Earlier in the day Brig. John Learmount, deputy commander of the Commonwealth force monitoring the cease-fire, painted a generally rosy picture of the first hours of the truce.

He said there had been no incidents at the 39 points where his forces are deployed for the guerrillas to assemble in camps under the terms of the London agreement.

"Every indication is that all concerned are making every possible effort to make the cease-fire work," he said.

One reason for the difference in interpretation lies in the function of the monitoring force. A British military official noted that the monitoring force can only deal with incidents in the areas where its 750 thinly spread troops in the field are operating.

The Rhodesian police are responsible for general law and order, including attacks on farms which have been commonplace.

The military official said the police would be expected to report any such violations to the cease-fire commission, consisting of Commonwealth officials and representatives of the two hostile military forces. The commission has yet begun its work.

Meanwhile, the police are continuing to report such violations to the Rhodesian military. Its communiques, which technically fall under the authority of the British governor, Lord Soames, continue to refer to the Patriotic Front forces as "terrorists."

Brig. Learmont, giving an example of how the cease-fire was working, said a group of local government officials and some guerrillas passed each other on a road in the northern area of the country and -- "both meticulously observed the cease-fire."

He also said the Front forces have indicated that they may help clear roads of mines in some areas -- a move that would be of great help to the monitoring forces in moving the guerrillas from rendezvous points to the assembly camps.

Learmont said there had been contacts with the guerrillas at many of the gathering points. Although he could only report that 100 had turned themselves in at an assembly camp in the north, he hoped to be able to provide more detailed figures Sunday.

The Rhodesian forces, he said, had disengaged and returned to their bases, where they are being monitored by about 200 Commonwealth troops as required under the cease-fire agreement.

The guerrillas have a week to assemble. After that, any forces, government or Patriotic Front, that are not in their designated areas will be regarded as illegal and subject to whatever action Lord Soames orders.