LONDON (AP) — British police have charged a 37-year-old man after products were injected with syringes in a few London supermarkets.

The Metropolitan Police force said Leoaai Elghareeb would appear in court Friday on a charge of contaminating or interfering with goods.

Elghareeb was arrested after a man entered three supermarkets in west London’s Hammersmith area on Wednesday and “injected an unknown substance into a number of food and non-food products,” police said. The force advised customers who had bought products at the stores on Wednesday evening to throw them away.

Police said the motive was so far unknown but “there is no evidence the man was working as part of a group.”