MINNEAPOLIS - The two passengers most seriously injured in this week's tour bus crash near Austin are improving.

A Mayo Clinic spokeswoman says 87-year-old Prem Deep and 80-year-old Helen Eubank, both of Rochester, are in serious condition. They had been in critical condition Thursday evening.

Two people were killed in the crash of the Strain Bus Line coach on Wednesday afternoon. The bus was carrying passengers back home after an outing to an Iowa casino.

Bus company officials have said the driver suffered a ruptured aneurysm just before the crash. State investigators have said they can't confirm that and determining the cause of the crash could take weeks.