Afghanistan's armed forces marked the 11th anniversary of the country's Marxist revolution Wednesday, holding a military parade a day early to avoid anticipated attacks by Moslem guerrillas.

As soldiers and war machines coursed through the central Eidgah Square, where Afghanistan declared its independence in 1919, insurgents fired a rocket into the capital. There were no immediate reports of casualties.Hundreds of the 40,000 conscripts defending the government of President Najib marched past the leadership in an hourlong parade modeled after Red Square observances of May Day and Revolution Day.

But the low-key observance of the Saur (April) Revolution that installed a Marxist government was scaled back dramatically, about one-fifth the size of last year's parade, military officials said.

"We did it for security reasons. We didn't want to take any chances," said one officer, insisting on anonymity.

There had been speculation in recent weeks that the guerrillas would launch an assault during the observance, prompting officials to move up the military parade a day early.

The Soviet Red Army pulled out of Afghanistan on Feb. 15, leaving the Afghan armed forces to face the insurgents alone for the first time in nine years.

Thousands of government soldiers are deployed around Jalalabad, the capital of Nangarhar Province and 40 miles from its eastern neighbor, Pakistan.