The AirBaltic flight was en route from Riga to Moscow when the incident occurred, RIA Novosti reported Monday.
"The aircraft of AirBaltic carrier, which took off on Sunday at 10:45 p.m., local time, from Riga to Moscow's Domodedovo airport returned to Latvia," the passenger said.
"As the second pilot announced on the speaker phone, the plane returned because the first pilot suddenly felt not well," the passenger said.
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