Abdellatif Merdas, a Moroccan member of parliament, shot dead in Casablanca, according to police
The 53-year-old, a politician with the liberal Constitutional Union party, was gunned down late on Tuesday near his home in the well-off southern district of Californie.
His assassins fled the scene, but police said on Wednesday they had arrested a 27-year-old man suspected of links to the assault.
A raid on the suspect's home came up with two shotguns similar to the one used in the attack, police said.
The assault is believed to be criminally motivated.