A rollover shortly after 2 p.m. on Interstate 19 near Nogales Sunday injured four people, authorities said.
The rollover occurred southbound on I-19 at kilometer 25, a Department of Public Safety official said.
The interstate was closed at kilometer 29 for two helicopters to land to airlift patients to a hospital, the DPS official said.
The interstate is expected to be open before 4 p.m.
No further information was immediately available.