Authorities are asking "the entire nation" for help finding a missing 2-year-old girl after the arrest of a man suspected of fatally shooting her mother in Milwaukee this week, the city's police chief said Friday.

Chief Alfonso Morales said the suspect, Dariaz Higgins, has been providing police with information on the whereabouts of his daughter, Noelani Robinson, but it all has "proven to be untrue."

"The search to find Noelani has become a game to him. It's obviously apparent that he truly doesn't care about Noelani," Morales said.

Authorities have not said when or where Noelani was last seen.

Higgins, of Miami, is accused of fatally shooting 24-year-old Sierra Robinson and wounding one of her friends Monday. Police arrested him Wednesday and prosecutors have charged him with first-degree murder.

Prosecutors said in charging documents that Higgins traveled to Milwaukee to give Noelani to Robinson but it's unknown if Higgins actually brought her with him. Police said Higgins was Robinson's pimp and they had been romantically involved, but were no longer together. Robinson left Noelani with Higgins when she moved to Las Vegas last month but wanted her back, authorities said.

According to charging documents, Higgins, Robinson, and her friend spent time driving around together in Milwaukee doing drugs Monday, before Higgins took them to an apartment building where he told them Noelani was. Prosecutors said Higgins shot Robinson and her friend when they got out of the car.

Police have said Noelani may be in Minnesota, but Morales emphasized she could be anywhere because Higgins has ties in several states. Morales suggested Noelani could be in the hands of human traffickers, but declined to provide details for why investigators believe that, other than to say "that's the world that these two individuals lived in, the victim and the suspect."

The FBI, which is aiding in the search, is offering a $5,000 reward for information that leads authorities to Noelani.