*

Trong died of unspecified 'serious illness'

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President To Lam has temporarily taken over his duties

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US, China sent messages of condolence

(Updates throughout, adding reactions from U.S., China and

Vietnamese people and institutions)

By Phuong Nguyen and Francesco Guarascio

HANOI, July 19 (Reuters) - Vietnam's ruling Communist

Party chief Nguyen Phu Trong died on Friday after holding the

country's most powerful position for 13 years during which he

oversaw fast economic growth, a years-long anti-graft crackdown

and a pragmatic foreign policy. He was 80.

Trong's duties have been temporarily assigned to President

To Lam, a rising star within the party who could further

consolidate his powers if he is allowed to keep the two roles.

Trong died in the early afternoon "due to old age and

serious illness", the Communist Party said in a statement on its

website, without elaborating further on the nature of the

illness.

The statement cited information from Trong's medical team,

saying he died "after a period of illness, despite being

wholeheartedly treated by the Party, the State, a collective of

professors, doctors, leading medical experts".

Lam had taken over Trong's duties on Thursday as the party

chief was ailing. The party will now need to decide whether Lam

will be formally appointed as acting party chief until the

current term for the post expires in 2026, or whether it will

elect a new head before then from within its ranks.

Although Vietnam officially has no paramount ruler, Trong

was the country's most powerful figure as party general

secretary and had been in the post since 2011.

He secured a third term in 2021 after a rule limiting

holders to two terms as party boss was waived, demonstrating his

strength and significant political clout in a party that has

ruled unified Vietnam for nearly half a century.

But in recent months, he appeared fragile in public events

and missed several top-level meetings.

A consolidation of power under Lam was seen by some business

people and analysts as potentially positive to speed up

decision-making in the Southeast Asian nation, which is home to

large factories of top multinationals, including Samsung

, Intel ( INTC ), Canon and Apple's ( AAPL )

top supplier Foxconn.

A clear shift to Lam's leadership "could moderate political

instability and factional infighting, at least in the short

term," said Peter Mumford, an expert on Southeast Asia at the

Eurasia Group, noting that would be beneficial to economic

growth.

But some diplomats and activists saw also risks of a

crackdown on civil liberties and a drift toward more autocratic,

China-style rule, if Lam were allowed to concentrate more

unchecked powers in his hands, in a break with the party's

tradition of collegial decision-making.

After Trong's death was announced, public events were

cancelled across the country until July 25 while state-run

websites had their banners turned black and white.

State broadcasters ran a documentary about Trong titled:

"General Secretary Nguyen Phu Trong: a steadfast, intellectual,

exemplary leader".

Bars in the capital, Hanoi, declined to serve drinks or play

music on Friday evening. Several Vietnamese Facebook users

changed their profile picture into a national mourning flag.

MARXIST-LENINIST

Trong was educated in the Soviet Union and was regarded as a

Marxist-Leninist ideologue, but he nonetheless nurtured ties

with the United States.

In 2017 he unleashed what many saw as a China-style

crackdown on corruption, known as "blazing furnace", under which

hundreds of officials were investigated for graft and many

forced to quit, including cabinet ministers, a parliament

chairman and two state presidents.

The operation had a chilling effect on investment.

Lam, a former chief of the powerful internal security

agency, has been a key player in that campaign and was elected

president in May after his predecessor resigned amid accusations

of unspecified wrongdoing.

Trong hosted both U.S. President Joe Biden and China's

leader Xi Jinping in Hanoi last year, boosting relations with

both countries despite increasing tensions between the U.S. and

China.

The U.S. embassy in Vietnam said in a statement Trong

was a "visionary leader who for decades served as a bridge

between Vietnam and the United States of America", and praised

him for being the first Vietnamese party leader to visit the

United States.

China's Communist Party also sent a message of condolence to

Vietnam, calling him a "staunch Marxist" and "a good comrade,

brother and friend," state media reported.