Hong Kong CNN Business  — 

Fears of political unrest have forced the cancellation of one of Hong Kong’s biggest money makers: The city’s weekly horse races.

The Hong Kong Jockey Club, which holds a government-granted monopoly on gambling, said it was canceling its weekly races on Wednesday because of an “imminent threat” to the safety of racegoers, jockeys and employees.

The Jockey Club says it is the largest single taxpayer in Hong Kong. According to the organization’s website, it contributes 16.3 billion Hong Kong dollars ($2.1 billion), or 1.3%, to the gambling-mad territory’s GDP.

“Our concerns are tied to potential social unrest in the vicinity tonight, the very real threat of a disturbance or possible violence at Happy Valley Racecourse, and uncertainty regarding transportation in and around” the area, a Jockey Club spokesperson said.

Protestors had earlier threatened to disrupt Wednesday’s races, a night set to feature a horse belonging to pro-Beijing lawmaker Junius Ho.

It is the latest blow to Hong Kong’s economy linked to a political crisis that has lasted for months. Pro-democracy protestors in the city have taken to the streets for 15 straight weekends.

The unrest has dragged on other sectors of Hong Kong’s economy, including the city’s restaurant and hotel industry. The international airport was also briefly shut down last month.

The Jockey Club, meanwhile, contributes about 13 billion Hong Kong dollars ($1.7 billion) a year to public revenue through direct and indirect taxes.

“Its contribution to the GDP is over half that of the restaurant and hotel industry and about two-thirds that of the communications industry,” the Jockey Club states on its website.

Horse race betting at the Jockey Club totaled more than 125 billion Hong Kong dollars ($16 billion) for the fiscal year that ended in June, according to the organization’s annual report.

Betting turnover on races from last Wednesday came in at 1.1 billion Hong Kong dollars ($140 million), according to the Jockey Club. This Wednesday is also the first time since Britain handed Hong Kong back to China in 1997 that a race has been canceled because of social and political unrest.

“The cancellation of the race meeting tonight is based on concern about public safety,” the Jockey Club said in a statement. “Financial aspect is not a consideration. In fact, there will be a replacement meeting later.”

The organization said bets made on Wednesday night’s races will be refunded.

The Hong Kong protests were originally sparked by a controversial bill that would allow extradition to China, but has since grown to include demands for more democracy and an independent investigation into alleged police brutality against protesters.

The city’s economy was already under pressure from the US-China trade war and slowing consumption in China. The government announced last month that it is pumping billions of dollars into its economy to avert a recession.

CNN’s Isaac Yee contributed to this report.