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China's earthquake monitoring centre has said that there were no warning signs prior to the quake.
Experts interviewed by The Straits Times agreed, as they say there is currently no way of accurately predicting an earthquake.
Others, however, believe there were ominous signs.
Professor Chu Tzu-how of the National Taiwan University said an unusual burst of radio waves - seen by some scientists as an early sign of big tremors - was detected prior to the Sichuan quake.
'But the signals were not strong enough for the mainland monitoring stations to file an early warning,' he said.
Prof Chu also conceded that even if an early warning had been filed, the authorities would probably not have issued an alert because the prediction technique is 'immature', with an accuracy rate of only 60 per cent to 70 per cent.
Other experts, like Professor Pan Tso Chien from the Nanyang Technological University, said that even if China had an early warning system, it would have made little difference, because residents would have 'a few seconds at best' to react.
When earthquakes first occur, they send out 'ripples' which travel quickly through the ground, explained Prof Pan. These are followed soon after by destructive shockwaves which travel more slowly.
This time lag gives people little precious time to react - and only if they are at least 1,000km away, he said. Seismic waves travel at 6km per second.
'For ground zero like Wenchuan province, these systems would have been little help,' he said.
Japanese earthquake experts say that despite advances in seismological research, tremors in general still cannot be predicted.
'The big difference between the monitoring systems of Japan and China is that we have more seismographs and more GPS observation points than China,' pointed out Associate Professor Kei Katsumata of Tokyo University's Earthquake Research Institute.
'But that does not mean that we have a better ability than China to predict earthquakes,' he said.
Another expert said China could also face problems in disseminating seismological data.
'China and Japan basically have the same sort of detection and monitoring systems. But Japan is much smaller and the Chinese problem could be one of speed of information dissemination,' said Assistant Professor Fumihito Yamazaki of Nagoya University.
Professor C.F. Lee, an earthquake expert at the Hong Kong University, told The Straits Times that no country in the world has been able to reliably predict a quake.
'An earthquake typically takes place tens of kilometres below the Earth's surface. We cannot put instruments deep enough in the ground to define the conditions of an earthquake occurrence,' he said.
The Sichuan quake occurred 10km underground.
But Internet forums across China are abuzz with chatter about other 'earthquake omens'.
Scores of Web users reported that days before the ground shook, hundreds of toads had descended upon the streets of Mianyang, a city about 100km away from Wenchuan county, the epicentre of the quake.
A blogger from Shandong wrote that his animals had been restless weeks before the earthquake.
But the local earthquake monitoring centre did not believe him, he wrote. 'They ridiculed me and accused me of making up stories.'
Most seismologists are sceptical about using animal behaviour to predict earthquakes.
Countries like Japan and the United States have spent decades and billions of dollars in attempting to predict earthquakes - including studies on animal prediction - but most of it have been in vain, Prof Lee said.
Without conclusive studies, scientists would be wary of making predictions because errors bred scepticism and complacency among the public.
There are also economic consequences to consider, Prof Lee pointed out.
'Predicting an earthquake means you have to shut down factories, companies, and so on. Nobody - not even the United States - would dare to 'jump the gun' in the face of huge economic losses.'
ADDITIONAL REPORTING BY TANIA TAN
