Beijing authorities on Friday condemned what they said is the "vicious use" of Hong Kong children by pro-independence forces to oppose the national security law being drawn up for the SAR.
Both the Hong Kong and Macau Affairs Office (HKMAO) and Beijing's liaison office in Hong Kong issued statements condemning a proposed referendum to decide whether school pupils should boycott classes to protest against the law.
In an article titled "Chop off the black hand, save the kids", the HKMAO warned that independence activists are trying to use children to stop the law's passage, while they themselves are busy fleeing overseas.
In particular, it criticised Joshua Wong and Isaac Cheng from the pro-democracy group Demosisto for using the Hong Kong Secondary Students' Action Platform to hold the referendum.
"Some extended their black hands into schools, and treating the students as 'artillery shells' and ‘tools' to prevent the NPCSC from passing the legislation. How malicious their intention! What despicable behaviour! The work of Demosisto’s Joshua Wong and Isaac Cheng will add to their criminal records."
It also lambasted the city's education system, saying it has deviated from the correct direction of One Country Two Systems, with "pro-independence and pro-violence thinking" spreading on campus.
The liaison office also attacked the class boycott proposal.
It said some political bodies have brought politics into campus, dealing a heavy blow to teaching and learning.
The office said it firmly supports the SAR government in stepping up education on the constitution, the Basic Law, and national security.
In response to being named in the HKMAO statement, Wong said he feels Beijing is hitting out at him because he has been doing a lot of advocacy work to bring international attention to Hong Kong's plight.
Wong also said he thinks there's a high chance Demosisto will be banned by the authorities, but said the group will "never kowtow to China".
Cheng, meanwhile, accused the central government of interfering in local education matters, saying he fears this will only get worse once the national security law is enacted.
"There will be a lot intervention inside schools and teachers will no longer have the courage or space to express their views," he said.