Father who intentionally crashed into restaurant, killing daughter and daughter-in-law, was mentally ill: Pastor Police say the father went in with his family, then left and drove into them.

A former police officer charged with intentionally plowing his car through a North Carolina restaurant and killing his daughter and daughter-in-law had been suffering from deep mental illness, his pastor said Monday.

Roger Self and 16 members of his family had gone to the Surf and Turf Lodge in the Charlotte suburb of Bessemer City after attending church on Sunday and were enjoying a meal when he suddenly got up, went to his car and drove it at full speed through the front window and into a table where his family was seated, police said.

Killed in the incident were Self's daughter, Kate Self, a sheriff's deputy, and his daughter-in-law, Amanda Self, an emergency room nurse, said Austin Rammell, pastor of the Dare to Venture Church in Dallas, North Carolina, where 62-year-old Roger Self was a longtime member.

Self's wife, Diane Self, and son, Josh Self, a police officer, were critically injured in the incident, which occurred around noon on Sunday.

"That was actually set up by Kate to just have a good time with her dad," Rammell said of the family gathering during a news conference Monday. "She wanted to have all the family there to have a good time with her dad."

He said Kate Self, 26, was seated at the table next to her fiance, Alex Burns, a police officer in Gastonia, North Carolina, when her father's car came through the restaurant window and wiped out their table, Rammell said.

"What happened yesterday was not a testimony of Roger Self, but a testimony of mental illness that absolutely overtook him a little over two months ago," said Rammell, who described Self to ABC News as his "best friend."

Roger Self has been charged with two counts of murder, the Gaston County Sheriff's Office said. He is being held in Gaston County Jail without bond and is expected to appear in court on Monday.

"He deeply loved his family. He deeply loved the daughter he killed. He deeply loved the daughter-in-law he killed," Rammell said.

He said Roger Self was a retired Gaston County police officer who founded his own private investigation business, Southeastern Loss Management.

Rammell said Self was also a former youth pastor at his church and had helped countless people across Gaston County overcome problems.

"Roger has been an icon in this community for decades," Rammell said. "There is a list a mile long of the people this man has sacrificed to make their lives better. He has walked with people through some of the darkest times imaginable and never once stopped to ask for credit or applause."

He said a little over two months ago, Self told him he was suffering from severe mental health problems and had concluded that he was no longer capable of running his business.

"He was suffering from severe depression and severe anxiety," Rammell said. "And by severe, I mean severe. This wasn't your normal, what you and I would go through when something bad happened in our life. This was severe and it was a roller coaster and the last few days it went from bad to really bad."

He said he and Self's family tried to get him treatment and that Self had been seeing a psychiatrist and was on antidepressants and anti-anxiety medication.

"But finding actual help for mental illness is a task of itself. If I break my leg I go to the ER. If I got a temperature and my stomach hurts and I think I got the flu, I call my family doctor," Rammell said. "But who do you call when you wake up every morning and you feel like somebody has a gun to your head and they're going to squeeze the trigger. Who do you call when you wake up every morning and you feel everybody in your family died, but you don't know why you feel that way."

He said Self's relatives told him that the Sunday restaurant outing had been going well.

"They were laughing and they had ordered their drinks and they had some appetizers and Roger got up," Rammell said. "Some of them thought he was just going to leave and come back. He'd get really anxious around people. And so they began noticing his car out in the parking lot had circled, and the next thing you know he came through the window."

According to Caleb Martin, who was busing tables at the Surf and Turf Lodge, the driver plowed through the front of the restaurant at full speed.

"I walked over to my station and I heard a loud boom," Martin told ABC station WSOC-TV in Charlotte. "It went straight through. There's a doorway. There is a wall and he drove in another room."

Gaston County Sheriff Alan Cloninger said Kate Self had been a member of his agency for four years. She started out as a detention officer and worked her way up to deputy and corporal.

"Tragic, tragic loss of life,” Cloninger said. "I'm asking people just to keep the family in your prayers, and the sheriff's office, because we're suffering right now."

Rammell said he was set to officiate Kate Self's wedding to Alex Burns in September.

"The family and the rest of this church firmly believe that Kate Self and Amanda Self are basking in the glory of heaven," Rammell. "We're all grieving deeply, painfully, totally confused, totally incapable of understanding this."

ABC News' Brendan Rand contributed to this report.