Tens of thousands of Taiwanese people rallied in the capital Saturday to demand the government heed the lesson of a Japanese atomic crisis and scrap the island's nuclear facilities, organisers said.

On the streets of Taipei protesters waved placards and flags painted with slogans such as "No Nuke, No fear" and "No Nuke for Our Children" as they gathered at a square outside the presidential office.

Worries about Taiwan's atomic facilities have grown since a 9.0-magnitude earthquake and tsunami struck Japan on March 11, 2011, crippling a nuclear power plant in Fukushima.

"Like Japan, Taiwan is an island with many earthquakes and I think it is just too dangerous to build a new nuclear plant near Taipei," said high school student Lu Pei-ying.

The Taipei event, which took place as three other rallies were held simultaneously across the island, drew an estimated crowd of more than 50,000 people, according to organiser Green Citizens' Action Alliance.

Police estimates of the crowd size were not immediately available.

Taiwan lies near the junction of two tectonic plates and is regularly hit by earthquakes. A tremor of 5.6 magnitude shook buildings in Taipei on Thursday.

Last month, Premier Jiang Yi-hua said for the first time that the government may support holding a referendum on the future of the fourth atomic plant ---- under construction since 1999 and still not completed -- amid growing public concern.

Organisers of the rally urged the government to immediately slam the brakes on the plant and move to completely stop using nuclear energy.

"It is unnecessary to hold the referendum as public opinion opposing nuclear energy is evident in many recent surveys. The government should terminate the nuclear project without further ado," said organiser Joanna Feng.

More than half of Taiwan's public want construction of the fourth nuclear plant, near Taipei, to be halted due to safety concerns, according to two surveys released on Thursday.

The three existing nuclear plants supply about 20 percent of Taiwan's electricity. Construction of the fourth was originally due to be finished by 2004, but political wrangling has delayed the project.