SAN DIEGO >> Maksim Derzhko calls it one of the most terrifying experiences of his life. A longtime opponent of Russian President Vladimir Putin, he flew from Vladivostok to the Mexican border city of Tijuana with his 14-year-daughter and was in a car with seven other Russians. All that separated them from claiming asylum in the United States was a U.S. officer standing in traffic as vehicles inched toward inspection booths.

The emotions are “hard to put into words,” he says. “It’s fear. The unknown. It’s really hard. We had no choice.”

The gamble worked. After spending a day in custody, Derzkho was released to seek asylum with his daughter, joining thousands of Russians who have recently taken the same route to America.

Even before Russia’s invasion of Ukraine led to punishing sanctions from the U.S. and its allies, the United States was already seeing an increase in Russian asylum-seekers. More than 8,600 Russians sought refuge on the U.S. border with Mexico from August through January — 35 times the 249 who did so during the same period a year earlier. Nine in 10 used official border crossings in San Diego.

Migrants from other former Soviet republics follow the same route in lower numbers, though some authorities are now anticipating more Ukrainians. The U.S. admitted a Ukrainian family of four on humanitarian grounds Thursday after twice blocking her.

Russians do not need visas to visit Mexico, unlike the U.S. Many fly from Moscow to Cancun, entering Mexico as tourists, and go to Tijuana, where they pool money to squeeze into cars they buy or rent. Adrenaline rushes as they approach San Diego’s San Ysidro border crossing, where about 30,000 cars enter the United States daily.

Concrete barriers funnel 24 lanes of traffic to a border marked by a few rows of yellow reflector bumps — like the ones that divide highway lanes — before vehicles reach inspection booths. A buffer zone separates the bumps from the inspection booths.

Migrants just have to reach that buffer zone to claim asylum on U.S. soil. But U.S. officers stationed on the Mexican side of the border first try to block them, peering into vehicles, motioning motorists to flash travel documents and stopping cars they deem suspicious.

“It was a very scary moment for all of us to experience,” Derzhko, who crossed in August, said in an interview at his home in Los Angeles. “The children with us, everyone was very worried, very much.”

Russians swap travel tips on social media and messaging services. One unidentified man narrated his trip from Moscow’s Red Square to a San Diego hotel room, with layovers in Cancun and Mexico City. His YouTube video shows him confessing to nerves after buying a used car in Tijuana, but he says later in San Diego that everything went smoothly — despite two days in U.S. custody — and that others considering the journey shouldn’t be afraid.

Russians are virtually guaranteed a shot at asylum if they touch U.S. soil, even though President Joe Biden has kept sweeping, Trump-era asylum restrictions. Border agents can deny migrants a chance to seek asylum on the grounds that it risks spreading COVID-19. But cost, logistics and strained diplomatic relations make it difficult to send people of some nationalities home.

Russians and others from former Soviet republics favor driving through official crossings, rather than trying to cross illegally in deserts and mountains. They generally do not hire smugglers, but “a facilitator” may help arrange travel, said Chad Plantz, special agent in charge of Homeland Security Investigations in San Diego.

While Moscow to Cancun is the most common route, some Russians fly from Amsterdam or Paris to Mexico City and then go to Tijuana, Plantz said.

It has produced some tense confrontations.

In one, a 29-year-old Russian man accelerated after passing the reflector bumps at San Ysidro on Dec. 12 and slammed the brakes, causing a sedan with six Russian asylum-seekers to hit him from behind. An officer fired four shots but no one was injured by gunfire, according to CBP, which says the incident is under investigation.

The SUV driver hit the gas in a state of excitement when he saw an opening between lanes, his lawyer, Martin Molina, told a judge earlier this month. Eleven other Russians, including the man’s wife, 5-year-old daughter and year-old son were in the SUV. Passengers raised their hands and yelled, “Asylum!”

“All that he saw were the bright lights of San Ysidro,” Molina said. “He wanted to get there.”

The judge ordered the driver released after nearly three months in jail. The Associated Press is not identifying him at the request of Molina, who said his client feared exposure may jeopardize his safety. The man, who opposed Russian intervention in the Chechnya region, planned to seek asylum with his family in Brooklyn, New York.

Other incidents have raised security concerns, Plantz said. Also on Dec. 12, the driver of a car with migrants from Ukraine and Tajikistan ignored an officer’s orders to show identification and struck the officer’s hand with a car door mirror when accelerating past him, according to court documents.

“They’re probably a little disoriented themselves, not sure exactly what they’re doing, but they are failing to yield, hitting the gas, blowing through,” Plantz said.

A federal judge in San Diego has ruled it is illegal to block asylum-seekers but has not given specific instructions, allowing authorities to continue their practices. Erika Pinheiro, litigation and policy director for Al Otro Lado, an advocacy group that sued over asylum limits at border crossings, said U.S. authorities coordinate with Mexican officials to keep migrants from reaching the buffer zone.

Yuliya Pashkova, a San Diego attorney who represents Russian asylum-seekers, traces the spike in arrivals to the imprisonment of Russian opposition leader Alexei Navalny last year. Asylum-seekers include Putin opponents, gay people, Muslims and business owners who have been extorted by authorities.

“When they think of America, they think of freedom, democracy and, frankly, a good economic situation,” she said.