A Maryland family called 911 over and over again as 40-year-old Marlon Somarriba had trouble breathing. They got a busy signal, his brother said.

Somarriba, of Rockville, Maryland, died after the Montgomery County 911 system failed for two hours late Sunday and early Monday.

Somarriba was undergoing kidney dialysis and had been doing well, his brother, Luis Somarriba said. But late Sunday night, he began having trouble breathing.

"He said a couple times, 'Help me,'" Luis Somarriba told News4's Jackie Bensen his father told him. He fought tears as he spoke Monday night alongside his parents.

Courtesy of family

The family dialed 911 over and over again from their cellphones and the landline in their home, but they got a busy signal, Luis Somarriba said. They called for more than an hour, he said.

Finally, Luis Somarriba called the Rockville City Police Department directly. They dispatched an ambulance, which arrived at the same time Luis Somarriba finished his frantic drive to the home where his brother lived with their parents.

"The medic said to me, 'I'm sorry, but your brother is gone,'" he said.

The 911 system failed between about 11:10 p.m. Sunday and 1:10 a.m. Monday, Montgomery County officials said in a statement issued Monday afternoon.

Investigators believe the 911 system shut down to prevent overheating when air conditioning equipment failed, officials said. That 911 system was a backup for the primary system, which was being upgraded.

A 91-year-old woman from Olney, Maryland, also died during the 911 outage. Information on the circumstances of her death was not available immediately.

Montgomery County Executive Ike Leggett said an investigation is underway.

"We will have answers as to a) whether or not there's a correlation between the deaths, b) what we have done wrong, if anything, and c) how we can prevent this in the future," he said.

For now, the Somarribas are in mourning.

"I never in my life knew that a 911 phone was not working at all," Luis Somarriba said.