(Border Report) — Two vehicles that attempted to speed past a California border crossing before an officer opened fire were carrying a total of 18 Russian immigrants including young children.

The “use of force incident” shut down several lanes at the San Ysidro Port of Entry for about eight hours from Sunday night into Monday morning.

U.S. Customs and Border Protection said that shortly after 9:30 p.m., a border officer spotted a Ford SUV and a Mercedes sedan speeding toward the primary inspection area.

The CBP officer, who inspects vehicles before they reach the primary insection, fired four rounds and struck the Mercedes, which then slammed into the SUV after it abruptly stopped.

The gunshots didn’t hit anyone. However, two of the occupants in the Mercedes sedan suffered minor head contusions.

In the two vehicles were 18 undocumented immigrants from Russia — 12 in the SUV and six in the car — including children younger than a year old. The adults were between 21 and 53 years old, and the oldest child was 14.

The drivers of both vehicles, both men in their 20s, have been arrested and face charges of “bringing in and harboring” certain noncitizens.

The San Diego Police Department and the CBP Office of Professional Responsibility will investigate the incident. Additionally, CBP said the agency’s National Use of Force Review Board reviews all incidents involving the use, or attempted use of deadly force, to determine whether the actions of CBP personnel involved in the incident complied with all relevant agency policies.

CBP said a third vehicle carrying undocumented immigrants from Russia eventually stopped at the primary inspection area. The black Dodge Durango had five adults ages 20-34, one 5-year-old, and one 17-year-old inside.