A moderate earthquake measuring 5.2 struck the New Zealand city of Christchurch on Monday, exactly a month after the country's worst quake in nearly eight decades, US scientists said.
The epicentre of the latest quake was relatively shallow at a depth of just nine kilometres (six miles) and was located only 18 kilometres west of the main city on New Zealand's south island, the US Geological Survey said.
It struck at 10:21 pm local time (0921 GMT).
There was no immediate indication of damage and no tsunami warning was issued.
It is the latest in a series of tremors following the quake on September 4, which caused no deaths but damaged around 100,000 homes, as well as rail lines and other structures. A state of emergency was imposed for over a week.
The lack of casualties then contrasted starkly with the mass loss of life regularly caused by quakes elsewhere in the Pacific region, an area known for its geological volatility and sometimes dubbed the "ring of fire".
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