LONDON (AP) — A British man who targeted schools and businesses with threatening letters in a six-week terror campaign in 2013 was sentenced Thursday to more than four years in prison and an additional five years over a sexual assault in 1988.

Woolwich Crown Court in east London heard that Gary Preston sent 42 envelopes containing white powder, which was later found to be talcum powder, and threatening messages that caused concern at the targeted venues. Some of the envelopes had small texts in Arabic on white paper, such as “Think fast, you have seconds Inshallah.”

Among the venues targeted in the fall of 2013 were the big Westfield shopping centers in east and west London, schools and colleges in Essex, which is east of the capital, and the Premier Inn hotel at London’s Stansted Airport.

Preston was arrested in September 2020 and pleaded guilty to 21 charges in August of last year.