Police in Flagstaff, Arizona USA on Saturday identified 29-year-old Joanna Wheaton as the bicyclist killed in a crash late Friday that injured several other riders.

It is the second death of a cyclist in less than a week in the southwestern state.

Wheaton was out for an group ride with five other cyclists when a tow truck driver ran a red light and plowed into the group, according to police.

A total of six cyclists were struck, with Wheaton pronounced dead at the scene. The other cyclists were taken to hospital where four still remain under care.

Officials on Friday identified the tow truck driver as 58-year-old Normand Cloutier of California. He has since been arrested and charged with causing a death by a moving violation.

Wheaton was a doctoral student at Northern Arizona University who organised one of the first pedal powered music concerts in the USA. As an outspoken activist fighting climate change, she believed, “If you have enough bikes, you can do some really exciting things with them.”

PHOTOS: J. Wheaton, Flagstaff Police Department

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