BEIJING (AP) – Zhao Ziyang, the former Chinese Communist Party leader who helped pioneer reforms that launched China’s economic boom but was ousted after the 1989 Tiananmen Square prodemocracy protests, died today at a Beijing hospital. He was 85.

The cause of death wasn’t immediately announced, but the official announcement of Zhao’s passing said he suffered from multiple ailments of the respiratory and cardiovascular systems. The official Xinhua News Agency said he died “after failing to respond to all emergency treatment.”

“He was very peaceful,” said Frank Lu, a prominent Chinese human rights activist who said he had spoken to Zhao’s daughter Wang Yannan. “He was surrounded by all his family.”

Lu spoke by phone from Hong Kong.

Zhao had lived under house arrest for 15 years. A premature report of his death last week prompted the Chinese comment to break its long silence about him and disclose that he had been hospitalized.

Zhao, a former premier and dapper, articulate protege of the late supreme leader Deng Xiaoping, helped to forge bold economic reforms in the 1980s that brought China new prosperity and flung open its doors to the outside world.

In the end, he fell out of favor with Deng and was purged on June 24, 1989, after the military crushed the student-led pro-democracy protests. He was accused of “splitting the party” by supporting demonstrators who wanted a faster pace of democratic reform. Zhao had lived under house arrest since then.

During the Tiananmen protests, Zhao called for compromise and expressed sympathy for some of the student’s demands. But his adversaries, led by Premier Li Peng, overruled him, called in the military and used the turmoil to attack Zhao and his supporters.

Zhao was last seen in public on May 19, 1989, the day before martial law was declared in Beijing, when he made a tearful visit to Tiananmen Square to talk to student hunger strikers. He apologized to the students, saying “I have come too late.”

Reports said he occasionally traveled to the provinces. He sometimes was sighted teeing off at Beijing golf courses or paying respects at the funerals of dead comrades, but otherwise remained hidden.

Usually seen dressed in tailored Western suits, Zhao served as premier in 1980-1987, then took over as general secretary of the Communist Party, the most powerful post in China.

He helped initiate sweeping changes that invigorated an economy mired in the ruins of the 1966-76 Cultural Revolution. Austere central planning gave way to material incentives and market forces that made China the world’s fastest-growing economy.

Those changes also brought inflation, income gaps between the rich and poor, corruption and other problems that Zhao would be blamed for when the conservatives drove him from power.

Zhao’s 1989 downfall was not his first. Mao’s youthful “Red Guards” dragged him from his home in Guangzhou in 1967 and paraded him through the streets with a dunce cap on his head before sending him off for years of internal exile.

The son of a landlord, he was born in 1919 in Henan Province. He joined the Communist Youth League in 1932 and became a full-fledged party member in 1938.

An agriculture expert in a country in which 80 percent of the people are rural, Zhao spent most of his career in regional government and party posts.

In the early 1950s, he directed a harsh purge in Guangdong province of cadres accused of corruption, ties to the Nationalists on Taiwan and opposition to land reform.

In 1957, he oversaw a rectification campaign in which 80,000 officials were sent to the countryside to live, work and receive criticism.

After four years in disgrace during the Cultural Revolution, he resurfaced in 1971 as a party secretary in Inner Mongolia. He won favor for his agricultural management there and in the southern province of Guangdong in 1971-75.

Zhao was named party secretary and governor of Sichuan, China’s most populous province, in 1975. With Sichuanese Deng’s backing, he dismantled the communist commune system, restored private plots and sideline rural businesses, raised farm prices and revived bonuses for extra work.

His pragmatic policies there turned food shortages that had left people on the verge of starvation into bumper harvests. Between 1977 and 1980, Sichuan’s farm output went up 25 percent and industrial production rose 81 percent. The “Sichuan Experience” became a model for the nation.

Zhao was known as a solid believer in the party. But he defined socialism much differently than Mao and other leftists.

“Of course we must keep to the socialist road. But what is socialism?” Zhao said in 1979. “The hallmark of socialism is the public ownership of the means of production, and the principle of socialism is “to each according to his work.”‘

Deng brought Zhao to Beijing in 1980 as a vice premier and member of the party’s powerful Politburo.

Six months later, he was named premier, becoming a role model for the younger technocrats installed by Deng in key positions to carry out his ambitious modernization plans.

But the reforms’ expansion to urban areas sparked overheating of the economy in late 1984 and 1985, forcing Deng and Zhao to slow the pace of growth.

In November 1987, Zhao was named general secretary of the Communist Party following the ouster of Hu Yaobang, who was blamed for pro-democracy student unrest.

Little was known about Zhao’s personal life. A 40-minute-a-day jogger, he once revealed in an interview that he sometimes argued with his family at the dinner table and liked his grandchildren.

He was known to have been married twice and had four sons and a daughter. His second wife was Liang Boqi.