French counter-terrorism prosecutors have opened a judicial investigation after a knife attack south of Lyon left two people dead on Saturday.

In a statement, prosecutors said charges will be pressed later Wednesday against the assailant, who was arrested by police minutes after the attack as he was kneeling on the sidewalk praying in Arabic.

Initial investigation suggested that the assailant acted alone, prosecutors said.

Magistrates are considering charges of murder or attempted murder with terrorist intent.

Read more: ABC News