Christchurch - A series of strong earthquakes struck the New Zealand city of Christchurch on Friday, rattling buildings, sending goods tumbling from shelves and prompting terrified holiday shoppers to flee into the streets. There was no tsunami alert issued and the city appeared to have been spared major damage.

Initial reports said one person was injured at a city mall and was taken to a hospital, and four people had to be rescued after being trapped by a rock fall. But there were no immediate reports of serious injuries or widespread damage in the city, which is still recovering from a devastating February earthquake that killed 182 people and destroyed much of the downtown area.

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© Stringer/New Zealand/ReutersDust rises from rocks falling from a cliff in the Christchurch suburb of Sumner moments after the earthquake struck.
The first 5.8-magnitude quake struck Friday afternoon, 16 miles (26 kilometers) north of Christchurch and 2.5 miles (4 kilometers) deep, the U.S. Geological Survey said. Minutes later, a 5.3-magnitude aftershock hit. About an hour after that, the city was shaken by another 5.8-magnitude temblor, the U.S.G.S. said, though New Zealand's geological agency GNS Science recorded that aftershock as a magnitude-6.0. Both aftershocks were less than 3 miles (5 kilometers) deep.

Updated: USGS aftershock data here

Power was reported out in some neighborhoods, and the Herald said that liquefaction of the ground had occurred in some of the city's eastern suburbs. Sewer lines broke, goods fell from shelves in stores, and large cracks opened in some buildings, the Herald reported.

About 60 people were treated for minor injuries, including fractures, injuries sustained in falls and people with "emotional difficulties," Christchurch St. John Ambulance operations manager Tony Dowell told The Associated Press.

"We have had no significant injuries reported as a result of the earthquakes today," he said.

Christchurch International Airport was evacuated. A Qantas flight from Sydney was diverted to Wellington, the Herald said. Airport authorities said they hoped to reopen the airport after checking buildings and other facilities for damage. In a tweet at 9:18 p.m. EST, airport officials said that "we hope this will happen in a few hours."

Newstalk ZB reported that debris had fallen from the Catholic cathedral on Barbados Street.

Radio New Zealand News reported that Warwick Isaacs of the Canterbury Earthquake Recovery Authority said buildings in the city's center were evacuated as a precaution.

"It ... started slow then really got going. It was a big swaying one but not as jolting or as violent as in February," Christchurch resident Rita Langley said.

"It was incredibly violent," one caller told Radio New Zealand.

"All the water in my birdbath slopped out and I could hear everything falling over inside. When I walked inside, the cat streaked out the door, ornaments were all over the floor, contents of the pantry were lying on the floor, a little bit of smashed glass and picture frames lying over."

The shaking was severe in the nearby port town of Lyttelton, the epicenter of the Feb. 22 quake.

"We stayed inside until the shaking stopped. Then most people went out into the street outside," resident Andrew Turner said. "People are emotionally shocked by what happened this afternoon."

The area has recorded more than 7,000 earthquakes since a magnitude-7 quake rocked the city on Sept. 4, 2010. That quake did not cause any deaths. But the earthquake that hit Christchurch on Feb. 22 killed 181 and caused damage initially estimated at up to $12 billion. It was the second deadliest quake ever recorded in New Zealand; one in 1931 in Hawke's Bay killed 256 people.

The USGS told NBC News that the quakes on Friday could be classified as aftershocks of the February killer.

Christchurch is on the east coast of New Zealand's South Island.