Hong Kong, Jan 16 (IANS): Police in Hong Kong has arrested 10 members of a radical anti-government group, with the suspects believed to be linked to a powerful pipe bomb seized earlier, it was reported on Thursday.

The force made the first arrests on Tuesday in a subdivided flat in Mong Kok and in Ho Par village in Sheung Shui, detaining four suspects, three of whom were students, the South China Morning Post said in a report.

The fourth suspect was found in an apartment that police described as a makeshift laboratory for making bombs.

The bomb, the first such improvised explosive device found in the city, was also recovered.

Some 40 grams of low explosives were inside the bomb, but it remains unclear what the substance was.

Six more suspected members of the group were arrested on Wednesday as police continued their operation and raided several flats citywide. The arrested included students and a kindergarten teacher.

Speaking to the media on Thursday, Senior Superintendent Chan Tin-chu said the device, discovered on Tuesday evening, was ready to be used, and was powerful enough to kill.

"The bomb was planned to be used at a large public event to attack police or their facilities, and cause a large number of casualties," the South China Morning Post quoted the officer as saying.

There have been a series of bomb threats in recent months, which police have said were linked to the ongoing anti-government protests that have rocked the city since June 2019.

In December, two home-made devices were found on school grounds while another three men were arrested for testing explosives less than a week later.