Walsh, 59, worked at a church in Syosset. She was in Water Mill on a retreat with other nuns in her order, the Sisters of Mercy. She was found lying next to a road. Detectives found a car with front end damage about a half-mile away.
Police declined to say how they concluded Ixpec-Chitay was the driver. They didn't release an address for him but said he frequents Water Mill and Riverhead. A possible Riverhead phone number for him was disconnected.
During her 10 years of working at St. Edward Confessor Church in Syosset, Walsh ministered to the sick and dying, trained young people to join the altar service and played other roles, Deacon Jim Murphy said. Her death was "an almost undefinable loss to our parish," he said.
Walsh, who went by Jackie, previously taught theology and was a campus minister at Our Lady of Mercy Academy in Syosset, according to the Diocese of Rockville Centre. She also was a youth minister for a time at Our Lady of Mercy Church in Hicksville, the diocese said.
A graduate of Springfield College, she entered the Sisters of Mercy in 1981 and earned a master's degree in theology from St. John's University, the diocese said.
Police are asking anyone with information about the wreck to call 631-702-2230.
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