Republican Ben Carson temporarily suspended his US presidential bid Tuesday when four members of his campaign team were in a serious car accident in Iowa, where the first votes in the nomination process will be cast.
A van transporting the group "hit a patch of ice and flipped on its side where it was struck by another vehicle," Carson's campaign said in a statement.
One volunteer was being transported to a trauma center in Omaha, Nebraska, while three others including a campaign staffer who was driving the vehicle were being checked at an Iowa hospital.
"I'm suspending all campaign activities today due to a car accident involving members of our team," Carson said on Twitter.
His campaign said Carson will travel to Omaha to be with the injured volunteer's family, the campaign said.
Rivals Marco Rubio, Ted Cruz and Rick Santorum all tweeted their support for Carson's campaign team after the accident.
Carson, a retired neurosurgeon, is among 12 candidates seeking the Republican presidential nomination in 2016.
Many of them are barnstorming Iowa in harsh winter weather as they seek to secure support in the run-up to the February 1 Iowa caucuses, the first votes in the presidential nomination process.
Carson is running fourth in Iowa, according to a poll average compiled by RealClearPolitics.com.