Singapore - Two months after the death of a foreign construction worker under the wheels of a bus in Singapore's Little India district triggered a major riot, an official Committee of Inquiry has begun its investigation into the city's first outbreak of civil unrest in four decades.

At least 70 witnesses - including officials, police and foreign workers accused of involvement in the December 8 riot, in which vehicles were set alight and nearly 50 police officers injured - are expected to give evidence over the next four weeks.

The bus driver and his assistant, who were arrested initially on suspicion of causing death by a negligent act, but have already been cleared, are also expected to appear.

"The Attorney General's Chambers will be leading the evidence," the government said in a statement.

On the first day of the hearing Wednesday, Senior State Counsel David Khoo presented an opening statement broadly explaining the evidence, which will cover the events surrounding the riot and some of the possible factors and circumstances that may have led to it.

Foreigners do not have an inherent legal right to work and stay in Singapore. Foreign workers must know that if they flout our rules, they do face repatriation. - Teo Chee Hean , home affairs minister

The four-member committee convened amid tightened security in Little India, one of Singapore's most vibrant districts and popular not only with the foreign workers who gather there on their day off, but tourists and Singaporeans as well.

The area has been designated a special policing zone with increased patrols, more CCTV surveillance cameras, and restrictions on the sale of alcohol, which the government has said contributed to the rioting.

A new law that could come into force in March is expected to give police the power to search anyone they deem a risk to public order or suspect of carrying alcohol.

'Safety and security'

"Foreigners do not have an inherent legal right to work and stay in Singapore," Home Affairs Minister Teo Chee Hean told parliament last month. "Foreign workers must know that if they flout our rules, they do face repatriation. We need to be strict about this to maintain the safety and security of our society."

Business student BJ Chia was at his post as a valet at a popular Little India restaurant on the night of the disturbance. Hearing the commotion, he ran across the road to see what was going on and videotape it.

"My mind just went blank," Chia told Al Jazeera on the ground floor of the public housing block, where he lives with his parents. "I didn't think whether they might hurt me. I just felt I had to record it. I never thought I would see anything like this in Singapore."

Chia says the crowd was extremely emotional and some of the men were in tears; their attention focussed on the rear left of the bus where fellow worker Sakthivel Kumaravelu was pinned underneath. But some were also violent. Chia's footage shows a group of men smashing the front windscreen of the bus, despite the desperate efforts of another man to stop them.

The student asked his girlfriend to upload what he'd shot to Facebook; one of scores who shared their material on social media networks that night. The next day, police officers visited his home, taking a statement and asking him not to distribute his footage.

The authorities also moved quickly against the workers.

Riot policemen watch burning vehicles in Little India [Reuters]

Teo told parliament in January that police interviewed about 4,000 workers in their dormitories or at their work sites in the two weeks after the riot.

Some 213 people were issued police cautions, but allowed to stay, 57 were given "stern warnings", deported and banned from ever returning to Singapore, while the remaining 25 were charged in court. Two have been found guilty and given 15-week-jail terms for "failing to disperse".

'Kneejerk reaction'

Some Singaporeans worry the response has focused too much on security, noting the already-considerable legislation relating to public order and calling on the authorities to postpone the introduction of the new bill.

The new law "proposes to give the Executive extensive powers, some of which are unprecedented in current legislation, and all of which are not subject to judicial oversight", said activist Vincent Wijeysingha, one of five civil society activists calling on the government to consider the bill more carefully and slow its passage through parliament.

At Tuesday's reading, MPs from the Workers Party voiced their opposition to the bill, calling it a "kneejerk reaction".

Wijeysingha is also among those who hope the inquiry will look more closely into the daily lives of the hundreds of thousands of poorly paid workers in the city. Some take two years simply to repay the fee of the agent that recruited them.

Healthserve is a charity that provides medical assistance and operates drop-in centres for workers from India, China and Bangladesh.

"Urban life is very harsh," co-founder Tang Shin Yong told Al Jazeera. "They (the workers) have to negotiate so many different things – language, culture, work, exploitation. It's a risk they take."

Providing what Tang calls a, "human touch," the group, made up of local volunteers, teaches the workers English and computer skills. The Bangladeshi men watch sport and drama on Youtube, catch up with news from home and share stories. Most have been in Singapore for around seven years, rarely having an opportunity to visit the wives and children they've left back home. The centre has become their surrogate family.

Singaporeans don't want to do hard work. We depend on foreign workers. Without them we wouldn't have our MRT or our high-rise buildings. - Irene Yeoh , liquor store owner

"I never did anything (before)," said 32-year-old Akbar Ali, who's been in Singapore for six years but only started visiting the centre six months ago. "I just sleep in my room. Now I can use the Internet, Facebook and find out what's going on in my country. We're all brothers and can take care of each other."

Poor conditions

Some dormitory operators have started to introduce more activities and improve facilities for their workers. Westlite, which provides beds for 23,000 workers in four dormitories across the city state, says it will spend 20 percent more on leisure activities and entertainment events for its residents in 2014. The government itself has set up two recreation centres.

Still, for many workers, home remains a stuffy room crammed with bunk beds. For others, it's a converted factory with 250 people on each floor and no cooking facilities.

Workers remain in Singapore only at their employer's discretion. Permits can be cancelled online, although workers do now have an opportunity to alert immigration to their plight at the point of departure, according to activists.

The inquiry's not due to file a report on its findings until June. It's not clear yet whether the document will be made public, but some Singaporeans say the riot should serve as an opportunity for the country to think more deeply about the way foreign workers are treated.

Irene Yeoh and her two brothers have operated a liquor store in Little India for 40 years. Boxes of beer are stacked at the back of the colonial shophouse around the corner from the scene of the riot. One wall is lined with shelves of vodka, whisky and liqueurs. Some of the bottles are so dusty they look like they've been there as long as the shop.

Now, after selling a can of beer to a regular on the first day the new alcohol restrictions were introduced, the family's lost its licence to sell alcohol. Yeoh and her brothers are angry, but not with the workers, many of whom were their regular customers.

"Singaporeans don't want to do hard work," she said. "We depend on foreign workers. Without them we wouldn't have our MRT or our high-rise buildings."