Axel Rudakubana, the 18-year-old accused of stabbing to death three young girls at a Taylor Swift-themed dance class in the U.K., was charged with possessing terrorism-related material and producing a toxin after an al-Qaeda training manual and a highly toxic poison were found in his home.

The stabbing in Southport, a town on the U.K.’s western coastline, ignited far-right riots across the country after a storm of misinformation emerged online that Rudakubana was a newly-arrived immigrant to the country. And now, some right-wing British lawmakers have launched fresh accusations of a government “cover-up.”

Rudakubana is already charged with the three murders of Bebe King, 6, Elsie Dot Stancombe, 7, and Alice da Silva Aguiar, 9, the attempted murders of ten others, and possession of a knife.

On Tuesday, police said that two recent discoveries in Rudakubana’s home in Banks, around 6 miles outside Southport, prompted them to slap on new the new charges – ricin, a toxic poison found in castor beans, and a pdf file of “Military Studies in the Jihad Against the Tyrants: The Al-Qaeda Training Manual.”

Rudakubana appeared in court on Wednesday via a video link from Belmarsh Prison. As in his initial appearance, he pulled his shirt over his nose to hide his face.

His trial is scheduled for January.

Police push back against cover-up accusations

At a news conference, police shot down allegations that they concealed information about the case and begged the public not to jump to conclusions.

“You may have seen speculation online that the police are deciding to keep information from the public,” Merseyside Police chief constable Serena Kennedy said. “This is certainly not the case.”

Ricin was not found at the site of the July attack, Kennedy said. She urged people not to speculate about the motive behind the attack, since the terrorism charge Rudakubana faces does not require police to establish that terrorism motivated him.

“My plea is to be patient. Don’t engage in rumor and speculation. Don’t believe everything you read on social media,” she said.

But news of the latest charges set off a surge of anti-immigrant rhetoric, as some lawmakers in the conservative Tory party accused officials of perpetrating a cover-up.

“We were told for months that this was not a terror related incident, and yet, yesterday, we learned for the first time that the suspect allegedly had access to al-Qaeda manuals and dangerous substances like ricin,” Robert Jenrick, a member of the U.K. parliament and candidate for Tory leadership said on British radio show LBC on Wednesday. “I’m asking the question: why was this information not put in the public domain sooner?”

Stabbing prompts ‘worst extremist violence’ in U.K. in decades

Days after Rudakubana’s arrest, far-right protests broke out across the U.K., spurred by claims that Rudakubana was a Muslim immigrant, which spread like wildfire across social media.

But Rudakubana was 17 at the time, and British law dictates that minors charged with a crime have a right to privacy. And he was born in Wales.

“The Southport attack was really a perfect case study of the very close relationship between online information and offline violence,” said Milo Comerford, director of policy and research at ISD, a counter-extremism think tank in the U.K.

By the end of august, police had made 1,280 arrests across the U.K. Hotels housing asylum seekers were set on fire and mosques were attacked in what Comerford called “some of the worst extremist violence we’ve seen in the U.K. for decades.”

Rudakubana’s possession of an al-Qaeda manual far from confirms assumptions about his motive that have echoed since the original attacks, according to Comerford. Michal Szewczuk, a 19-year-old white supremacist jailed in 2019 after calling Prince Harry a “race traitor” who deserved to be shot had a copy of the manual, and 18-year-old neo-Nazi Jack Reed consulted it as he plotted to firebomb synagogues before his conviction in 2019, according to ISD.

But the new charges against Rudakubana could “validate those perceptions that have already existed within communities, both online and offline,” Comerford said.

One lesson that Comerford said officials should take from the riots – holding back information doesn’t pay off.

Much of the continuing online outrage centered around perceived hidden information in the case. Although authorities didn’t want to compromise Rudakubana’s privacy or legal rights as a minor, Comerford believes they could have disclosed more to head off “conspiratorial language” and “claims that this somehow vindicates the rioters who have been jailed” now seeping into online spaces.

“It’s very complicated – the relationship between terrorism investigations and establishing motive,” he said. “It’s really important to provide as much clarity around that as possible, so that those who are looking to weaponize this to spread anti-Muslim sentiment, for example, are not able to do so.”