Some truckers found themselves in a sticky situation over the weekend as protesters angry about recent police killings tried to block highways, and in some cases succeeded. Photos show protesters climbing on top of tractors and trailers in some locations.

The shooting deaths of Philando Castile in St. Paul, Minn., and Alton Sterling in Baton Rouge, La., have, as ABC News put it, “set off a tumultuous chain of events and ignited a fierce debate over police tactics and race relations that continues to roil communities across the nation.”

In St. Paul late Saturday night, protesters caused an hours-long shutdown on part of I-94 west of downtown. Hundreds of protesters were spread across the eastbound and westbound lanes, according to published reports, with many throwing objects at police, who eventually used smoke to help disperse the crowd. About 50 protesters were arrested on I-94 and some police officers were injured.

In Memphis, Tenn., I-40 was blocked in both directions for about four hours Sunday evening after more than 1,000 people occupied the bridge over the Mississippi River.

Demonstrators in Oakland, Calif., blocked traffic along Interstate 880 Thursday night. Although the California Highway Patrol issued an alert around 9 p.m. asking drivers to use alternate routes, and commercial trucks were given permission to use Interstate Highway 580 on a temporary basis, some trucks were still stuck in the mess.

In Baton Rouge, La., police kept a group of protesters from entering I-110 late Sunday after a lengthy standoff. Some 30 to 40 people were taken into custody for trying to block a highway. One striking image of that confrontation, of a woman in a dress being confronted by police in riot gear, has gone viral on social media. Louisiana Gov. John Bel Edwards said at a late weekend news conference that he didn’t believe using riot gear to push protesters away from highway ramps was overly aggressive, according to the Associated Press.

In Southern California late Sunday night, protesters shut down a major intersection and blocked traffic on the 405 Freeway for several minutes.

In Atlanta Friday night, police kept protesters from entering the Interstate, but one local trucker on his regular route was caught in the downtown protest. WSB-TV2 in Atlanta spoke by phone with Chris Golden, who used the opportunity to promote his business as a recording artist. Footage showed people climbing on top of his truck and trailers, but Golden was supportive of the protesters, saying it was “all about unity,” noting that black and white protesters were both involved, calling it “a beautiful sight.”

On social media, some truckers said they wouldn't be so understanding and suggested they would not stop for protesters.