WASHINGTON — The Justice Department has opened a criminal investigation into a California congressman who faces allegations that he spent tens of thousands of dollars in campaign funds on family trips to Hawaii and Italy, private school tuition and dance competitions for his children, and even video games, officials disclosed Thursday.

Representative Duncan D. Hunter, a Republican from San Diego who was considered for several top national security posts in President Trump’s administration, became the latest in a string of at least eight current or former members of Congress to face criminal investigations over ethics issues in the last several years.

A five-term congressman, Mr. Hunter has already paid back $60,000 to his political campaign to correct what he said were mistaken payments for personal items.

But that has not cleared him of scrutiny.

The House Ethics Committee, which has been examining Mr. Hunter’s possible misuse of campaign funds, said in a statement on Thursday that it would put its review on hold at the request of the Justice Department.