A Chinese father who was jailed for campaigning over contaminated baby milk has suddenly dropped his plans to appeal, defence lawyers say.
Zhao Lianhai's son was one of about 300,000 made ill in 2008 by drinking infant formula tainted with melamine.
The industrial chemical was added to dairy products to make them seem high in protein.
Mr Zhao was jailed for two-and-a-half years for organising a parents' support group and campaigning for compensation.
He vowed to appeal when he was sentenced earlier this month.
But lawyers working for Mr Zhao told the BBC Chinese service they were blocked from visiting him on Monday to discuss his case.
Instead they were given a note, apparently from Mr Zhao, saying he no longer needed their services.
One lawyer, Li Fangping, told the BBC he could not tell if Mr Zhao wrote the message voluntarily because he was not allowed to see him in person.
Mr Li said he and his colleague, Peng Jian, then went to see Zhao Lianhai's wife, who also handed them a note saying they had been fired.
Both lawyers had already faced pressure to drop the case, and Mr Peng was detained and questioned by the authorities over the weekend, Mr Li said.
"I've never encountered a situation like this before," he told the BBC. "I'm powerless."
The melamine scandal in 2008 caused widespread public anger and sympathy for the victims and their families.
It led to a worldwide recall of Chinese dairy products and was a major embarrassment for the country's leadership, who vowed to tackle the problem and restore consumer confidence.
Mr Zhao was convicted of inciting public disorder for accepting interviews with foreign journalists, staging protests to bring attention to the issue, and organising a gathering of affected parents.
His sentence was criticised by international human rights groups.
In Hong Kong, 28 delegates to China's National People's Congress signed a petition pressing for his immediate release.
Despite the scandal two years ago, the Chinese authorities are still finding dairy products tainted with melamine.
In the latest report, state media say regulators are trying to recall a batch of contaminated drinks in central Hubei province.