WASHINGTON, March 10 (Xinhua) -- Former U.S. Vice President Joe Biden and Senator Bernie Sanders, two major candidates in U.S. Democratic presidential race, have cancelled their rallies scheduled for Tuesday night over coronavirus concerns.

The Biden campaign said they would "continue to consult with public health officials" on future events.

The Sanders campaign said in a statement that they will evaluate future events "on a case by case basis."

Their moves were seen as the first disruptions the outbreak has caused in the 2020 U.S. presidential primary.

Both the Sanders and Biden campaigns thanked supporters who planned to attend the events on Tuesday, a mini-Super Tuesday when six states -- Idaho, Michigan, Mississippi, Missouri, North Dakota and Washington -- were holding primaries for voters to select their preferred presidential candidate this year.

Sitting President Donald Trump is expected to win the Republican primaries as he is facing no major challenges in the party.

As of Tuesday, there were more than 900 confirmed cases of COVID-19 in the country, with at least 29 deaths, according to local media reports.