* Former deputy to meet ground commanders Friday -sources
* Move comes as scale and intensity of protests escalates
* U.S., Australia raise travel warnings over Hong Kong protests
* More weekend protests planned, including airport rally
* Almost 600 arrests since protests began in June
* Protest pamphlets describe a 'broken, torn-apart city' (Recasts with former police chief recalled from retirement to deal with protests)
By David Lague and Farah Master
HONG KONG, Aug 8 (Reuters) - The police commander who oversaw pro-democracy demonstrations that roiled Hong Kong in 2014 has been recalled from retirement to help deal with the violent protests convulsing the Chinese-ruled city, two sources with knowledge of the move told Reuters.
The sources, both senior government security officials, said former deputy police commissioner Alan Lau Yip-shing, planned to meet top-level ground commanders on Friday.
The move comes ahead of yet another weekend of protests across the former British colony, including a three-day rally at the international airport, that have prompted travel warnings from countries including the United States and Australia.
"The protests and confrontations have spilled over into neighbourhoods other than those where the police have permitted marches or rallies," said an advisory posted on the website of the U.S. State Department on Wednesday.
What began as protests against a bill that would have allowed people in Hong Kong to be extradited to mainland China for trial in courts controlled by the Communist Party have evolved into a broader backlash against the city's government, with flash mob-style demonstrations on an almost daily basis.
Lau's recall suggests the government lacks confidence in the capacity of the current police leadership to manage the response, the security officials said.
Hong Kong police and the government did not immediately respond to a request for comment.
The police have been increasingly targeted by protesters, who have hurled abuse at officers on the front lines and attacked them in online forums.
Activists accuse the police, who have fired rubber bullets and nearly 2,000 rounds of tear gas to disperse demonstrators, of using excessive force and have called on the government to launch an independent inquiry into their actions.
The violence has escalated rapidly in the past few weeks, with many protests degenerating into running battles between demonstrators and police, who have arrested nearly 600 people since June, the youngest aged 13.
The Hong Kong government and authorities in Beijing have condemned the violence and said they stand by the police and the city's embattled leader, Carrie Lam.
Lau, who retired in November, has been appointed deputy commissioner for special duties, which would give him responsibility for handling the protests, the sources said.
Officers who served with Lau during the pro-democracy protests in 2014 that paralysed parts of Hong Kong for 79 days but failed to wrest concessions from Beijing said he was respected by senior commanders for his leadership at that time.
He is widely seen as a decisive officer, according to senior security officials.
CHALLENGE FOR BEIJING
The protests pose the biggest popular challenge to Chinese President Xi Jinping since he came to power in 2012. Xi is also grappling with a debilitating trade war with the United States and a slowing economy.
China's Foreign Ministry lodged stern representations with the United States, urging U.S. officials to stop sending wrong signals to the "violent separatists" in Hong Kong. Local media have reported that a U.S. diplomat met democracy activist Joshua Wong in the city.
Hong Kong is facing its worst crisis since it returned to China from British rule in 1997, the head of China's Hong Kong and Macau Affairs office said.
Protesters who plan more action this weekend want Lam to categorically withdraw the extradition bill, and an independent inquiry into the government's handling of the controversy, among other demands.
Lam, who says the bill is dead but has not withdrawn it, visited some districts on Wednesday to speak with residents and inspect a police station recently targeted by protesters.
The government would put forward measures to improve people's livelihoods, she said after the visit.
Young people are at the forefront of the protests, worried about China encroaching on Hong Kong's freedoms and problems such as sky-high living costs and what many see as an unfair housing policy favouring the wealthy.
The normally efficient and orderly city has seen its transport network besieged and closed down by demonstrators and big-brand stores and popular shopping malls have been shut.
Three masked activists, who did not give their names, held a news conference on Thursday, their second this week and broadcast on domestic television channels, to criticise what they called arbitrary arrests and police use of tear gas.
"The continuation of such attempts at spreading fear and suppressing the freedom of press will eventually backfire on the government itself," one activist told the Citizens' Press Conference, a platform used by protesters.
"The ultimate victim of these tactics will be the police force's crumbling public image," the activist said in English.
The comments came after plainclothes police arrested a student leader from Baptist University, Keith Fong, on the grounds that laser pointers he bought were offensive weapons.
Several thousand black-clad Hong Kong lawyers marched in silence on Wednesday to call on the government to safeguard the independence of the city's justice department.
They fear prosecutions of arrested protesters are taking on an increasingly political slant. Many of those arrested have been charged with rioting, which carries a 10-year jail term.
Ahead of the airport rally, protesters circulated brightly-coloured pamphlets online to help tourists understand events.
"Dear travellers, please forgive us for the 'unexpected Hong Kong'. You're arrived in a broken, torn-apart city, not the one you have once pictured. Yet the city you imagined is exactly what we are fighting for," the pamphlets said. (Reporting by David Lague, Farah Master, Felix Tam, Anne Marie Roantree and Twinnie Siu Editing by Paul Tait and Darren Schuettler and Catherine Evans)