Real-life superheroes with names like Vortex, Midnight Highwayman and Fallen Boy patrol San Diego's streets at night armed with radios, first aid kits and self-defence weapons.

Xtreme Justice League San Diego
Members of the Xtreme Justice League stand watch on a street corner during a patrol in downtown San Diego, California. (L to R) Fallen Boy, Freedom Fighter, Mr. Xtreme and VortexMike Blake/Reuters

The Xtreme Justice League have a serious task at hand: they walk through dark, empty streets, check in on the homeless and even break up fights in their effort to stop violent crime in the city.

The league was started by Mr Xtreme in 2006. "I do this to make a difference. We have about 20 members that are committed to stopping crime and violence, making a difference, raising awareness and spreading good will in the community", he said.

Xtreme Justice League San Diego Mr Extreme
Mr Xtreme goes over his notes before he and the Xtreme Justice League speak to a local children's karate class about bullyingMike Blake/Reuters

"I've actually saved a life volunteering, so I know from true experience that what we do is very valuable and meaningful. If I was not there, this person might not have lived. So even if some people might think it's ridiculous, I know it's not."

Vortex says: "If there's a situation and the cops are not present we could always do a citizens' arrest or defuse the situation. We are the eyes and ears of the streets."

Reuters photographer Mike Blake spent time patrolling the streets of San Diego with the Xtreme Justice League.

Xtreme Justice League San Diego Freedom Fighter
Freedom Fighter looks out from behind his mask while on patrolMike Blake/Reuters
Xtreme Justice League San Diego Midnight Highwayman
Midnight Highwayman's glasses reflect the setting sun while on patrol a local street fair in San DiegoMike Blake/Reuters
Xtreme Justice League San Diego Fallen Boy
Fallen Boy of the Xtreme Justice League poses for a portrait before a late night patrol in San DiegoMike Blake/Reuters
Xtreme Justice League San Diego Fallen Boy
Fallen Boy of the Xtreme Justice League wears a chest plate as part of his costumeMike Blake/Reuters
Xtreme Justice League San Diego grimm
Grimm waits outside the Hall of Justice building for other members of the Xtreme Justice League to arrive for their weekly patrolMike Blake/Reuters
Xtreme Justice League San Diego
Women react as they walk past a patrol of the Xtreme Justice League in San DiegoMike Blake/Reuters
Xtreme Justice League San Diego
Fallen Boy, Freedom Fighter and Vortex are approached by some men during a patrol in downtown San DiegoMike Blake/Reuters
Xtreme Justice League San Diego Silver lining
Silverlining shows off his swollen lip after breaking up a fight while on patrol with the Xtreme Justice League in San DiegoMike Blake/Reuters
Xtreme Justice League San Diego
Grimm, Lobo and Freedom Fighter stop to check on a man sitting in a doorway late at nightMike Blake/Reuters
Xtreme Justice League San Diego
Fallen Boy, Mr Xtreme and Vortex approach a woman during a late night patrol in San DiegoMike Blake/Reuters
Xtreme Justice League San Diego
Mr. Xtreme, Fallen Boy and Vortex of the Extreme Justice League stop to help a man during a patrol in San DiegoMike Blake/Reuters
Xtreme Justice League San Diego
Midnight Highwayman, Mr. Xtreme, Light Fist and Spartan pose for a picture while on patrolMike Blake/Reuters
Xtreme Justice League San Diego grimm
Grimm checks his phone as he awaits the arrival of other Xtreme Justice League members outside San Diego's Hall of JusticeMike Blake/Reuters
Xtreme Justice League San Diego
Spartan, Fallen Boy and Light Fist walk past the courthouse to begin their night patrol in San DiegoMike Blake/Reuters