Hall of Fame pitcher and baseball analyst Pedro Martinez announced over social media that several of his family members were inside the nightclub that collapsed in the Dominican Republic.
"I still have family members that are still in the (rubble) and we don't know what happened to them," Martinez said in a video posted to Instagram.
The death toll is up to 124 people with at least 150 more injured following the accident at the Jet Set nightclub in Santo Domingo on Tuesday.
Martinez, a three-time Cy Young Award winner and eight-time All-Star, grew up in a suburb of Santo Domingo.
"It is with a heavy heart that it is my turn to actually send condolences to all our family members and the people here in the United States who have family over there," he said in the video.
"We're all sad, we're all affected by the tragedy. Our hearts are with you. We all are affected."
Former World Series champion Octavio Dotel and former MLB player Tony Blanco, who also played in Japan for the Chunichi Dragons and Yokohama BayStars, died due to injuries suffered in a mass casualty event.
Also among the deceased was the sister of Nelson Cruz. Nelsy Milagros Cruz Martinez was the governor of the Montecristi province in the country.
Dotel was reportedly alive when rescue crews located him and at least seven others, but authorities said Tuesday evening that he was declared dead upon arrival at a local hospital after being rushed to the medical center for treatment of serious injuries.
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