The man accused of shooting two National Guard members in Washington DC last week spent weeks at a time alone in a dark room and suffered "manic episodes" - according to comments written in 2024 by a case worker who helped the suspect's family with their relocation after they fled Afghanistan.

Rahmanullah Lakanwal is accused of carrying out an "ambush" that killed Sarah Beckstrom, 20, and seriously injured Andrew Wolf, 24.

Officials said the 29-year-old entered the US in 2021 as part of a programme for Afghans who had worked with American troops in Afghanistan.

According to the emails from last year that were obtained by BBC's US partner, CBS News, Mr Lakanwal struggled with his mental health.

In an interview on Sunday with NBC, Homeland Security Secretary Kristi Noem said that Mr Lakanwal had been "radicalised since he's been here in this country" and that officials believed this happened "through connections in his home community and state".

Mr Lakanwal, an Afghan national, entered the US as part of the Biden-era Operation Allies Welcome programme.

This was during the period after the chaotic US troop withdrawal from Afghanistan. As the Taliban took back control of the country, there were fears of retribution against individuals, such as Mr Lakanwal, who had co-operated with the US.

He applied for asylum in 2024, and his application was granted earlier this year, an official told CBS.

He lived with his wife and five children in Bellingham, Washington - a state on the other side of the country from where last week's attack took place.

A motive is not yet known, but a picture of Mr Lakanwal's life in the US has started to emerge through the emails that were sent last year to non-profit group US Committee for Refugees and Immigrants.