Washington (CNN) A Maryland Democratic gubernatorial candidate died suddenly Thursday morning after experiencing cardiac arrest, authorities said.

Baltimore County Executive Kevin Kamenetz, 60, awoke in his home outside of Baltimore around 2 a.m. feeling ill and was pronounced dead an hour later after being transported to St. Joseph Medical Center, the county said in a statement

Kamenetz joined the gubernatorial race last September. He was one of seven Democrats in a crowded primary field competing for the Democratic nomination to oppose Maryland's Republican Gov. Larry Hogan in the general election.

Of the field, Kamenetz, who served 16 years as a Baltimore County council member before becoming county executive, was one of only three Democratic candidates with elected experience and viewed as a leading contender. The Democratic gubernatorial primary is scheduled for June 26.

The night before Kamenetz died, he participated in a candidate forum in Prince George's County, Maryland, alongside other Democratic gubernatorial candidates.

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