With Russian forces poised to launch an all-out air and artillery assault on Grozny, the capital of Chechnya, the safe-passage route promised to thousands of trapped civilians barely functioned in the first 24 hours that it was open.

Three days of Russian delays in opening the escape path, bureaucratic tie-ups at a key checkpoint here, difficult terrain and continued Russian artillery fire along the way have limited civilians' flight from Grozny.

Only 200 refugees passed through this checkpoint by 3 p.m. today, the first full day the escape route was available, and Russian officials said only 150 crossed on Thursday. Estimates of the civilian population of Grozny run as high as 40,000, not including residents of outlying towns.

The Russians promised the safe exit route in leaflets dropped on Grozny on Monday, which warned that anybody who didn't leave the city by Saturday would be "destroyed." The leaflets guaranteed safe passage via a road passing through Pervomaiskaya, a town on Grozny's western outskirts.

Some may have fled Grozny since the ultimatum via another route, west to the neighboring Russian region of Ingushetia, even though fighting between Russian troops and separatist Chechen militants has continued along that path.

In Moscow, Russian Prime Minister Vladimir Putin said he had recently met with envoys representing Chechen President Aslan Maskhadov, but that the talks had gone nowhere. Russian military and political officials continued to give conflicting signals about whether an intensified offensive was about to commence against Grozny. [See story, Page A28.]

The escape route offered by the Russians is difficult to travel. The road passes over a mountain peak high above Pervomaiskaya, so many Chechens lacking vehicles or gasoline have to climb several arduous miles from the valley. A gentler valley road south of here is under Russian control and is not open to refugees.

If Russian forces are on the attack, as they were today, refugees risk being hit by artillery fire. Shells were launched this afternoon no more than 200 yards from the checkpoint here. Their target was Pervomaiskaya, several miles away, which lies along the escape route and is full of potential refugees who are now cowering for cover in basements and bunkers.

When reporters asked a Russian spokesman here why soldiers fired artillery along a route that was supposed to be safe for refugees to travel, the official, Col. Alexander Veklich, replied, "That's not artillery. We're using special explosives to dig trenches."

Russian officials said they meant Monday's ultimatum as a goodwill warning for civilians and a scare tactic aimed at rebels hiding in Grozny. It seems instead to have made civilians feel trapped.

"Word is spreading that the bombing is going to get worse," said Waha Ahmatov, a refugee from a Grozny suburb. "But people also fear they will get shelled on their way out. Look at what's happening today."

As Ahmatov spoke, a double blast from howitzers boomed out from the adjoining peak. In a half-hour stretch, the guns fired six times on Pervomaiskaya, 1,300 feet below.

"How are people supposed to come out of their homes with that going on? How?" an elderly traveling companion named Zena asked tearfully.

Russian officers who escorted reporters to the checkpoint today gave two different explanations about why the escape route was late in opening: computers didn't work, or rebels attacked refugees who tried to use it. One officer insisted it had been open all the time. The checkpoint's announced capacity is 3,000 refugees a day.

Veklich said the inconvenient mountaintop position was chosen because it's a "nice, clean area." On a clear day, like today, you can see Grozny.

Dozens of refugees who waited at the barricade to be processed today shivered in near freezing weather. Some had been standing there for three hours. Inspectors checked documents and kept a watch for guerrillas trying to sneak through.

Near the barrier, a middle-aged man in a minibus lay prone, his two legs caked with blood and riddled with shrapnel. His wife said he was hit by artillery two days ago. Russian soldiers in the valley near Pervomaiskaya refused to let them carry him out until today, she said. Before she could explain further, a Russian soldier at the checkpoint shooed away reporters, who were here on a trip organized by the Russian army. Twenty minutes later, the minibus was still parked in the same place.

Russia's ultimatum to civilians to evacuate Grozny or risk death attracted broad international condemnation, including Washington's. At stake in the fighting is Russia's drive to reconquer Chechnya, a breakaway region located 1,000 miles south of Moscow. Chechnya won effective independence from Russia in 1996 after a two-year war. Russian generals are eager to retake Grozny, to reverse their humiliating defeat in the earlier conflict.

Conquest of Grozny also would be a major political prize for Putin on the eve of parliamentary elections Dec. 19. Putin has been a key promoter of the war, which he says must be waged to fight international terrorism and to keep Russia whole. The Russian offensive was in large part a response to incursions by Islamic guerrillas from Chechnya into neighboring Dagestan and apartment house bombings in Moscow and other cities, which claimed nearly 300 lives, and that the Russians blamed on Chechen militants.

Russia insists it is not fighting the Chechen people, whom it regards as its citizens. Nonetheless, towns and hamlets all over Chechnya have been shelled and bombed, even though rebel positions mostly lie outside inhabited areas.

In Grozny, though, rebels hide within residential areas. To drive them out with infantry and house-to-house fighting would risk high Russian casualties. Analysts say the army wants to clear Grozny of civilians so it can fire at the city at will and expel the rebels without making a frontal assault.

One young Russian soldier near the checkpoint hinted at the difficulties troops might face if they invade on the ground. He said an armored unit tried to penetrate Pervomaiskaya a few days ago but was rebuffed by rebels. Eight soldiers died. Since then, artillery has rained on the town. "We'll kick them out eventually," the soldier said.

Russian forces hold roads and most villages around the capital. The army has positioned tanks, artillery pieces and multiple rocket launchers on hilltops and fields, all aimed at the capital, or on other unconquered areas.

Today, clusters of Russian tanks and armored personnel carriers scurried about muddy fields only three miles from Starya Sunzha, an eastern suburb of Grozny. The bearded commander, Col. Sergei Skiba, showed off trenches that once sheltered rebels. "They had dug these to last," Skiba said. "They thought we were weak. But we showed them our force beats their force."

Another commander, Col. Victor Yevtushenko, expressed eagerness to conquer Grozny. "If the government hadn't told us to leave in the last war, we would still be there," he said.

There is evident concern among Russian military officers that the controversy over civilians could stall the advance. Officials who spoke with reporters the past two days about the subject seemed exasperated, even tongue-tied. One officer, Gen. Vladimir Kovrov, who is in charge of civilian affairs, asserted that estimates of the number of civilians in Grozny were exaggerated. "There are only 4,000 civilians in Grozny," he said. "Anyone who wanted to leave has left."

Officials are battling hard to end perceptions that Russia is treating the Chechens badly. More than one half of Chechnya is under Russian control, and in those areas, the Russians are working to make towns and hamlets habitable. Electricity has been restored in many places, natural gas is flowing and schools opening.

Yet the civil mood remains sour, and has been further poisoned by the threats to step up bombing of Grozny. "We can't sit here comfortably knowing that the war is going to get worse somewhere else," said Hamid Olkhazur, a municipal worker in Lakha Nyovre, a town on the south bank of the Terek River. "We have our troubles, but that doesn't mean we can be indifferent to problems of others."

A young man who gave his name only as Murat said, "They keep telling us they mean to bring peace. But it is the peace of steel."

Chechens in town after town say they want a peaceful life, but chuckle at government pledges to bring law and order to Chechnya. "Just where is this order in Russia?" asked Poka Ubichal, a teacher who fled Grozny two months ago. "Do people have peaceful lives in Russia? I don't think they can bring us something they don't have themselves."