BEIJING (AP) ― Outspoken artist Ai Weiwei said Tuesday that Chinese authorities are now seeking $2.4 million in back taxes and fines from him, a sign that the government is not easing pressure on the dissident detained for nearly three months earlier this year.

Two officials from the Beijing Local Taxation Bureau delivered a notice to the artist Tuesday saying he owed just over 15 million yuan ($2.36 million) in back taxes and fines, Ai said in a phone interview. He had been served a tax notice in June for a slightly smaller amount.

Ai said Tuesday that he would not pay until police return his Beijing Fake Cultural Development Ltd. design company’s account books and he discusses the matter with his former office manager and accountant, whom he says he has not been allowed to see.

“We can pay this money, but we need to know why we have to,” he said. “We cannot just unwittingly hand over a sum of money. This would be irresponsible toward the country.”

Ai said he refused to accept Tuesday’s notice, which said he must pay the amount owed within about 10 days, or face unspecified further measures.

Ai’s detention earlier this year prompted an international outcry among artists, politicians and human rights activists, and Western leaders called it a sign of China’s deteriorating human rights situation. His family and supporters say he is being punished for speaking out about the Communist leadership and social problems.

Ai was released in June after spending nearly three months in secret detention without being charged. Ai’s family previously denied he evaded any taxes, and activists say the accusations were a false premise for detaining him. Before his own detention, he tracked the detention of other activists.

After Ai’s release, the Beijing tax bureau tried to serve him a notice seeking about 12 million yuan ($1.85 million), but representatives of the design firm challenged the bill and were told by Chinese officials that the company had not paid corporate taxes for a decade.