Mark Castillo of Rockville walked with his three young children Saturday afternoon through Baltimore's Inner Harbor, where tourists congregate along the city's waterfront promenade.
About 5 p.m., he checked into the Marriott Hotel near Camden Yards and took his children into Room 1060, a top-floor room with two beds.
An hour later, one by one, Castillo drowned his children in the bathtub, police said. When he was done, he laid their tiny, naked bodies on one bed: Anthony, 6, Austin, 4 and Athena, 2.
Then he swallowed 100 Motrin pills and cut himself in the neck with a steak knife in an apparent suicide attempt, police said. He woke up about 1 p.m. Sunday, after sleeping for hours - his dead children in the same room - and called the front desk, police said, to report what he had done.
Hotel security alerted police and paramedics and, using a master key, opened the door.
"I know what I did was bad," Castillo told medics who arrived first, according to police charging papers filed with the court. "I did it. I drown the kids last night around 6 p.m."
Yesterday, police charged Castillo with three counts of first-degree murder and a dozen related charges, including child abuse and assault. He was ordered held without bail and is scheduled to have a hearing in District Court today.
Since Saturday night, his estranged wife, Dr. Amy Castillo, had been calling police, desperately trying to find her children while fearing that he had followed through on his threats.
Yesterday, Amy Castillo, a pediatrician with Kaiser Permanente's Mid-Atlantic region, was in her Silver Spring home on Waterford Road.
A family friend, Cheryl Wharton, read a brief statement to reporters: "Amy Castillo asks for your continued prayers during this unspeakably difficult time. She is surrounded by family and friends and is coping as well as can be expected. We ask that members of the press respect Amy's privacy as she bears this solitary cross."
Beginning at 10:30 Saturday night, she had called Montgomery County police to report that her husband, who according to court documents has a history of mental problems, was late dropping off the children. But police told her they could not begin a search because Castillo had the legal right to be with them and he had made no new specific threats.
"Statements like that that would have ramped this investigation up were not made to police," said Lt. Paul Sparks, a spokesman for the Montgomery County Police Department. He said Mark Castillo's tardiness would not constitute a criminal act until the children were missing for 48 hours.
Still, Sparks said county police are reviewing how they handled Amy Castillo's calls.
"We are looking at our own response and what could have or should have been done that would have prevented this tragedy," Sparks said.
Police said yesterday in court papers that Castillo had waived his rights against self-incrimination and gave a taped confession to homicide detectives. He told them that the motive stemmed from a divorce and custody battle he was having with his wife, according to the charging document written by Detective Robert Ross of the homicide unit.
The mayor and the police commissioner called a news conference to discuss the killings.
"Cases like this one are difficult," Police Commissioner Frederick H. Bealefeld III said at a news conference. "They have an incredible emotional impact on everyone involved."
Added Mayor Sheila Dixon: "This tragedy makes one wonder and question why someone would do such and act. We will be asking ourselves why, why could someone do this to three innocent young children."
Mark Castillo, who had once lived in a van, recently rented a room from a Spanish-speaking family on Schuylkill Road in Rockville.
Yesterday, the owner, Maria Galvis, said she often saw the children when they visited with their father, whom she called "Mr. Mark."
"I can still see the children, and hear their voices," Galvis, a native of Colombia, said in Spanish. "Whatever Mr. Mark did, I still respect him. It's not up to us to judge him, because only God knows what went on in his heart at that moment."
Galvis described her tenant as "very educated, very proper and, above all, an excellent father." She said that whenever the children visited - usually twice a week - he made sure they ate nutritious food and that the floor on which they frolicked was clean.
"His children were his eyes," Galvis said. "He adored them. It's extremely hard for me to believe what happened."
Mark Castillo rarely spoke about his problems with his wife, Galvis said, although he made clear to her that he wanted to see the children more often and that the custody battle was arduous. Even then, she said, he never spoke negatively about his wife.
She said the police had been to her house twice, on Saturday and on Sunday, looking for Castillo and the children after they were reported missing. "Those children are three innocent angels, and now we have to pray for strength for these parents," Galvis said.
The family problems ran deep.
Over Amy Castillo's frequent objections during a long and bitter divorce and custody fight, Mark Castillo had visitation rights with the children. On Saturday he was permitted to be with them but was supposed to return them to her home by 8:30 p.m.
When he did not return, Amy Castello began calling the Montgomery County police. She made her first call about 10:30 p.m., said Lt. Paul Sparks, a spokesman for the county police. A half-hour later, she called again and police went to the Rockville home where Mark Castillo had rented a room.
"There were people there," Sparks said. "Police talked to them and determined that he and the children were not there."
The mother called police again at 9 a.m. Sunday and demanded to see an officer, who came and took a report. She tried reaching her husband on his cell phone, but failed. Police also tried to call his cell phone, but calls went straight to voicemail, Sparks said.