Police in the city of Chandler and state police ordered the evacuations of at least two hotels and businesses alongside I-10, Department of Public Safety spokesman Bart Graves said.
Chandler police moved people from hotels, homes and businesses within a 1-mile radius to the east of the freeway. The Phoenix Fire Department asked residents on the west side of the freeway to stay in their homes.
Horizon Community Learning Center, a K-12 charter school on the west side of the freeway, was closed for the day and students were sent home.
The evacuation orders were lifted about two hours after the crash after firefighters finally were able to move in and douse the flames.
The crash happened when a milk tanker rear-ended another tanker truck carrying 7,700 gallons of diesel gas byproduct and caught fire, Graves said. The driver of the milk truck was killed in the intense fire that sent flames skyward and black smoke hundreds of feet into the air.
The driver of the petroleum tanker was shaken up but uninjured and got out on his own, Phoenix Fire Department spokesman Capt. Scott McDonald said.
The crash happened at about 7:45 a.m. on westbound I-10 and snarled freeway traffic across the suburbs south of Phoenix. The freeway was closed in both directions from U.S. 60 south to the Loop 202 freeway. Both are major routes into and out of Phoenix from the south.
Firefighters were hampered by a lack of water along the freeway and had to bring in water trucks and firefighting foam to attack the flames, McDonald said.
It took fire crews about 10 minutes to douse the flames when they attacked it. Although the tanker carrying diesel fuel had burned furiously for nearly two hours when fire crews moved in, the flames were still fierce and showed no sign of letting up.
"It would have burned all day," McDonald said. "There was plenty of fuel to burn in that truck."
The eastbound lanes of I-10 were expected to reopen before noon, while the westbound lanes would be closed for hours as the debris was hauled away, officials said.