The Metropolitan Police was called at 1.08am on September 21 with reports of a man with a knife threatening people in Leicester Square.
At the scene officers discovered four men, aged in their 20s and 30s, suffering wounds.
Their conditions are not believed to be life-threatening or changing.
A 50-year-old man was arrested on suspicion of grievous bodily harm, possession of an offensive weapon, grievous bodily harm, affray, and possession of a Class B drug.
He has since been detained under the Mental Health Act.
A spokesperson for the Met said: "We were called at 01:08hrs on Sunday, 21 September to Leicester Square, Westminster to reports of a man with a knife threatening members of the public.
READ MORE: Notice issued for various Bromley road closures for gas works
"Officers atte