Anti-Trump protesters hurl rocks as Trump wins Washington primary

Protesters opposed to Donald Trump hurled rocks and bottles outside a rally he spoke at in New Mexico on Tuesday, the same day the bombastic billionaire won the Republican presidential primary in Washington state.

The victory brings Trump, the last Republican standing in the 2016 US presidential race, one major step closer toward clinching his party's nomination.

But the success was overshadowed by violent anti-Trump demonstrations in Albuquerque, in the southwestern state of New Mexico.

US Republican presidential candidate Donald Trump is the party's presumptive nominee, and while he is not officially the flagbearer yet he is on the cusp ©Brendan Smialowski (AFP/File)

Chaos erupted outside a Trump rally when protesters burst through metal barriers and tried to storm the city convention center, where the provocative Republican was speaking.

The crowd threw burning T-shirts, bottles and rocks at police, while police on horseback and officers wielding clubs used pepper spray and smoke grenades to try to disperse the crowd.

"Several #APB officers are being treated for injuries as a result of being hit by rocks. At least one subject arrested from the riot," Albuquerque police said via Twitter early Wednesday.

The protesters, several of whom waved Mexican flags, chanted expletives about Trump. Some also waved signs with expletive-laden anti-Trump slogans in Spanish.

Most of the protesters left before midnight, police said.

Trump has proposed building a wall on the Mexican border, suggested that Mexican immigrants were rapists and drug dealers, and urged the deportation of the 11 million undocumented immigrants in the United States.

New Mexico has the highest percentage of Hispanic residents -- nearly 50 percent -- of any US state, and polls show that Hispanics overwhelmingly oppose Trump's immigration proposals.

New Mexico Governor Susana Martinez, the nation's only Hispanic governor and head of the Republican Governors Association, has criticized Trump's remarks on immigration and was absent from Tuesday's event.

Trump addressed a rally of about 4,000 people but was frequently interrupted by protesters, the Albuquerque Journal reported.

Police managed to stop a group of about 100 protesters who had tried to storm the convention center when Trump was speaking, the newspaper said. Riot police were deployed soon after.

Several Trump rallies have drawn protests, including one in Chicago in March when his supporters clashed with protesters.

Trump has been criticized as inciting violence at his rallies.

- Trump's Washington victory -

US networks called the race in Washington state for Trump shortly after polls closed at 8:00 p.m. (0300 GMT Wednesday).

With more than two-thirds of ballots counted, Trump earned 76 percent of the vote.

"Thank you Washington! #Trump2016 #MakeAmericaGreatAgain," the candidate wrote on Twitter.

Trump is the Republican Party's presumptive nominee, and while he is not officially the flag bearer yet he is on the cusp.

He headed into the race in the northwestern state with 1,189 delegates, according to a CNN tally, just 48 delegates short of the 1,237 needed for the nomination.

Washington state had 44 delegates up for grabs. Trump will therefore cross the threshold and clinch the nomination on June 7, when California and four other states vote on the final day of the Republican primary contest.

The real estate mogul's former rival, Texas Senator Ted Cruz, as well as Ohio Governor John Kasich and retired neurosurgeon Ben Carson, were still on the Washington ballot even though they already dropped out of the race.

Trump, a political neophyte whose provocative campaign has turned American politics on its head, will be officially installed as the Republican presidential nominee at the party's national nominating convention in Cleveland, Ohio in July.

He pivoted to the general election weeks ago, relentlessly criticizing his likely Democratic rival Hillary Clinton.

The former secretary of state has returned fire, although she is still engaged in the final stages of her Democratic battle against challenger Bernie Sanders.

The senator from Vermont has an extremely narrow path to the nomination, and the math clearly favors Clinton.

Washington held its Democratic primary in March, and Sanders won it easily. But Clinton, like Trump, is close to becoming her party's flag bearer.

A supporter of Republican presidential candidate Donald Trump attends a fundraising event in Lawrenceville, New Jersey ©Eduardo Munoz Alvarez (AFP/File)