A toxicology report that would reveal whether Rodas had drugs in his system will not be available for a number of days, officials said.
Rodas, of Grand Island, Neb., boarded the bus in Cleveland. Knott said he was on his way to Washington, D.C., where his sister lives. A friend was supposed to pick him up at the bus station, he said.
The sister told police that her brother called her during a layover in Pittsburgh, Knott said. He said the sister told authorities that Rodas had been drinking.
She also said her brother had been treated for heart problems when he lived in El Salvador.
"Another problem for us was he was speaking, but he was speaking Spanish and no one on the bus spoke Spanish. So they didn't know what he was saying," Knott said.
After pacing up and down the isle while speaking Spanish, Rodas grabbed the steering wheel and tried to get off the bus, according to police reports. The bus driver pulled off Interstate 70 into a park-and-ride lot on Col. Henry K. Douglas Drive while Rodas tried to kick out the windows.
During the struggle, several passengers tried to restrain Rodas, holding his legs and arms.
When a state trooper arrived, Rodas collapsed and stopped breathing. Attempts to revive him failed.
Passengers told authorities that Rodas had behaved normally during the rest of the trip.
Knott said the other passengers continued their trip in another Greyhound bus while state police investigators documented the bus. He said it was returned to Greyhound later that morning after authorities took photographs and searched for other evidence.
"It's just in case there was something we missed," he said. "But that apparently was not the case."