Olathe ? Mourners gathered Thursday to grieve for five family members killed in a weekend fire.

The blaze early Oct. 16 in Olathe killed Matt and Rebecca Orr, both 46, and three of their sons: Benjamin, 18, Jeremiah, 16, and Kyle, 14. Another son, Justin, 23, escaped with a burned right hand and smoke inhalation.

He and his sister, Kameron, a Kansas University student, greeted the mourners after Thursday’s service at The Church of Jesus Christ of Latter-day Saints. The siblings plan to rent an apartment together and return to their college classes as soon as possible, said Ken Ross, a family friend and spiritual adviser.

In a letter read at the funeral, Gordon B. Hinckley, world leader of The Church of Jesus Christ of Latter-day Saints, commended the brother and sister for their strong and close-knit family.

He also told them the five family members would be reunited in heaven with another child, Melissa Orr, who died last year at 21.

The fire victims will be buried in Lake City, Fla.

Fire officials have said they think the fire was accidental, and on Thursday some electrical devices were sent to be tested. They were found in a first-floor room where investigators think the fire began.

“We’re sending them away to an independent laboratory so they can help us prove or disprove our findings,” said Mike Hall, an Olathe Fire Department spokesman. He would not say what the electrical devices were.

Hall said it could take the laboratory in Johnson County several weeks to evaluate and return the evidence.

Of the three fire alarms in the home, at least one sounded. That one, in the basement, alerted Justin Orr. He escaped but was unable to help other members of the family because of the thick smoke. Hall said a second alarm in the basement was not working.

Authorities hope the testing will help them determine whether a third alarm, on the second floor, sounded during the fire.