NEW YORK » The mother-in-law of an American missionary confirmed today that he was among those killed after al-Qaida fighters attacked a hotel and cafe in Burkina Faso’s capital of Ouagadougou.

Carol Boyle said Michael Riddering, 45, died in the Cappuccino Cafe, where he was to meet a group Friday that was going to volunteer at the orphanage and women’s crisis center he ran with his wife, Amy Boyle-Riddering.

Riddering arrived early and was in the cafe with a local pastor; when the attack started, they ran in different directions, Boyle said. The pastor had Riddering’s phone, and called Boyle-Riddering to say they were at the cafe and there was gunfire, but then the line went dead.

The pastor hid in the cafe; he survived. It wasn’t until a fellow Christian missionary found Riddering in the morgue on Saturday that they knew he was dead.

He leaves behind four children, two of whom were adopted from Burkina Faso.

“He was extremely well-loved and respected. He wasn’t a hypocrite, he wasn’t a two-face. He had his guiding light, and he followed it,” Boyle said by phone from her home in Weston, Florida.

Riddering, who once managed a yacht outfitting company in Cooper City, Florida, and his wife, a graphic designer, sold their property and possessions and moved to the town of Yako to run the Les Ailes de Refuge orphanage in 2011, Boyle said. The complex also includes a clinic, classrooms and a home for abused women and widows.

“They were looking forward to continuing to working in Burkina Faso and raising their children together,” a statement from Sheltering Wings, the missionary organization that sponsored the orphanage, said. “Tragically and unexpectedly, Mike’s life was cut short. We grieve with Amy and her family, and all who knew Mike.”

John Anderson, a Sheltering Wings board member, remembered Riddering as “a wonderful, godly man” who managed to find spare time to help teams of volunteers from other organizations who dug wells for local residents.

“During the Ebola crisis, when it was hard to find people to do the digging, Mike would go out and join them so they could continue doing the work,” Anderson said. “And that’s backbreaking work. He never stopped moving and never stopped helping.”

At least 28 people died in the attack by fighters, which triggered a siege lasting more than 12 hours. The dead, which included victims from 18 different countries, included the wife and young daughter of the Italian cafe owner, two French citizens, two Swiss citizens, and six Canadians.