Anti-Donald Trump protesters have lit fires and thrown bottles and rocks outside a rally in New Mexico.
Riot police responded with smoke canisters and pepper spray to bring crowds under control.
Mr Trump was declaring his love for New Mexico at the Albuquerque rally, but fiery prostetors outside showed the feeling wasn't mutual.
Hundreds of demonstrators turned violent, hurling burning tee-shirts, plastic bottles, and overturned rubbish bins.
Dozens of extra riot police were brought in and forced to use smoke canisters and pepper spray to bring the angry crowd under control, many of whom waving Mexican flags.
Back inside, Mr Trump was repeatedly interrupted by protesters who had to be forcibly removed by security officers.
Adding fuel to the fire was Mr Trump winning the Washington State Primary earlier in the day.
It puts him even closer to having the number of delegates he needs to become the Republican Presidential nominee.
Wednesday marked Trump's first stop in New Mexico, the nation's most Hispanic state.