DALLAS – Botham Shem Jean had a heart that led him to serve others.

The 26-year-old was active in his church and often led the congregation in song. He was a Harding University graduate and worked at ­PricewaterhouseCoopers in Dallas.

A Dallas officer who mistook Jean's apartment for her own fatally shot him around 10 p.m. Thursday, Police Chief Renee Hall said. The officer was identified as Amber Guyger, a four-year veteran of the force; she is expected to be charged with manslaughter.

Hall said Saturday that the Texas Rangers, who took over the case, asked her department to hold off issuing an arrest warrant because they need more time to look into information the officer provided during an interview.

The officer had finished a full shift and was returning to her apartment when the shooting occurred. Hall said it's still unclear what happened between the officer and Jean.

Mayor Mike Rawlings said Saturday that the shooting is a "very serious situation" for the city and described Botham Jean as a young professional and man of faith who was "exactly the sort of citizen we want to have."

Now his name has become yet another trending hashtag in a string of names of black men who have been killed by white police officers. Friends and family used social media to share their memories.

From the Caribbean island Saint Lucia, where much of his family still lives, he went to college in Searcy, Ark., and then moved to Dallas to be a risk assurance associate for PricewaterhouseCoopers.

"I always saw Botham around campus," Amy Johnson said on Twitter. "He always wanted to lead in chapel in whatever way he could. He was always so nice and so kind. He was definitely a light at Harding — one who I could never forget. Prayers for his family and friends."

Grant Smith, another classmate, said Jean was "a great Christian example and an inspiration to us all."

Smith created a GoFundMe to help the family cover funeral arrangements and travel.

"Botham was everything I wish I was and more," Aaron Young wrote. "He moved more people with his smile and his voice than I can possibly imagine. My heart goes out to his family. He was so so loved."

While in school, Jean was a member of the Good News Singers, a resident assistant and an intern for the Rock House campus ministry, the university said.

On April 9, 2014, Jean uploaded a video on YouTube during his campaign to be the university's student association president. "My whole platform has been to initiate a forum where students can talk freely and can express their views freely in a positive way," he says. "I think this whole concept of opening doors between faculty and students, I think that is going to have a significant impact on all students on campus because they can now express what they feel and we can use that to develop plans and initiatives that are going to affect their lives."

Jean said his ability to unify and motivate his classmates set him apart from his three opponents. "I want to serve. My heart and experience has led me to serve. I want every student at Harding to have the best Harding experience possible and go on to accomplish all of their dreams."

The Associated Press contributed to this story.