Hong Kong (CNN) - Four British citizens have been arrested by Chinese authorities in eastern Jiangsu province, the UK Foreign Office said Friday, two days Chinese police announced a drug raid there involving 16 foreigners.
In a statement Wednesday, Chinese police said they had arrested 19 people in Jiangsu, including 16 foreign citizens after they tested positive for illegal drugs.
Those arrested included seven teachers and nine foreign students, according to police in the city of Xuzhou. Police did not provide details relating to the specific nationalities of those arrested or the type of narcotic used.
In a statement on their social media, English language training provider, Education First (EF), said with "deep regret" that some of their teachers had been involved in the drug use.
CNN has reached out to EF for comment. The UK Foreign Office could not confirm whether the two cases were related, nor when the Britons were arrested.
"We are in contact with the Chinese authorities following the arrest of four British people in Jiangsu province, and are providing consular assistance," the Foreign Office said in a statement.
The Chinese government has little tolerance for the use or trafficking of any illegal drugs inside the country. Anyone found with more than 50 grams (1.76 ounces) of a controlled substance can face the death penalty.
Recent years have seen authorities in major Chinese cities step up their efforts to crack down on recreational drug use, including spot drug tests at bars and nightclubs.
In June, Chinese authorities said they had intercepted dozens of packages of "cannabis or cannabis products" connected to foreign students or Chinese students who had worked abroad.
According to Xuzhou police, one foreigner was under criminal detention while the other 18 suspects were under "administrative detention."
EF said it would immediately terminate the employment contracts with any employees who were confirmed to have used illegal drugs in China.
The news has been rapidly spreading on Chinese social media. State media tabloid Global Times claimed the case was leading some parents to call for a "nationwide inspection" of foreign teachers' qualifications.