By Chris Hogg
BBC correspondent in Hong Kong
A veteran Hong Kong politician has told legislators he quit his radio talk show because of warnings he would be in danger unless he toned down his anti-Beijing views.
Listeners and presenters challenge politicians on the talk shows
Allen Lee, who is also a member of China's parliament, the National People's Congress, said he quit after a number of people pressured him to keep quiet.
Four hundred academics have taken out an advertisement in a leading daily newspaper in Hong Kong expressing disquiet over the resignation of Mr Lee and two other high-profile talk show hosts.
Radio talk shows are relatively new in Hong Kong but have rapidly become an institution.
Some estimates suggest as many as one in six people here listen to them in the morning.
Ordinary people have the chance to air their views.
Politicians find themselves challenged rigorously by the listeners and the programmes' presenters.
But recently three talk show hosts have resigned, complaining of threats and intimidation.
This hearing by Hong Kong lawmakers was an attempt to find out what is going on.
Two of the hosts refused to attend, saying they feared for their safety.
But a third, Allan Lee, told the inquiry a retired Chinese official and other friends from the mainland had tried to persuade him to tone down his comments.
He refused and decided to quit, after one Chinese official remarked "your wife is very nice
and your daughter is very pretty".
Mr Lee did not name names but he said the Chinese authorities were more nervous than ever before about the results of this year's election for Hong Kong's mini-parliament, still three months away.
Fears for the future of free speech in the former British colony have prompted 400 academics to take out an advertisement in the most widely read Chinese daily newspaper here, expressing "shock and concern" about the talk show hosts' resignations.