Mitt Romney, the former Massachusetts governor and 2012 Republican presidential candidate, postponed announcing his plans for the Senate race in Utah in the wake of a deadly shooting at a Florida high school on Wednesday.

“As a father and grandfather, my heart aches for the victims of today’s tragic events,” Romney said in Twitter postings on Wednesday night. “Out of respect for the victims and their families, I will not be making an announcement tomorrow about the Senate race.”

A gunman killed at least 17 people at Stoneman Douglas High School in Parkland, Florida, when he opened fire with a semi-automatic rifle, the Associated Press reported. A 19-year-old former student at the school was taken into custody.

Romney, 70, has been widely expected to enter the Republican contest to succeed Senator Orrin Hatch, who has decided not to run for an eighth term.

Romney, a popular Republican who has been a scathing critic of President Donald Trump, would be an early favorite to win the seat. He has an established fundraising network, almost universal name recognition in the state and solid ties to The Church of Jesus Christ of Latter-day Saints, which is dominant in Utah.

The former private equity executive is also known in the state for taking over management of the troubled 2002 Winter Olympic Games in Salt Lake City.