South metro law enforcement officials are welcoming help from outside groups to combat sex trafficking, which they say is crucial in tackling the crime while finding victims the help they need.

The topic was at the center of the Dakota County Chiefs of Police Association's recent annual training event. For the first time, the training was co-sponsored by a ministerial association in Hastings, where an anti-trafficking coalition is linking the city's faith community with police and volunteers.

"You have no other criminal case that demands that kind of collaboration across disciplines," said Minneapolis police Sgt. Grant Snyder, who often trains and assists local police.

Snyder said community groups can help with the "gap work," the period between recovering a victim and building a case against her abusers. Hastings' Christian Coalition to End All Sexual Exploitation is establishing a crisis hot line and working on a program for schools.

Peter Wohler, executive director of the Annex Network in Minneapolis, said his organization helps put victims in transitional homes and link them with case workers and volunteers who can help find work or even guide them through grocery shopping.

Snyder called investigating sex trafficking "every bit and more complex than homicide cases." One search warrant served on a Facebook account returned 40,000 pages of evidence, he said.

Minnesota's homeless youth are most vulnerable to falling prey to traffickers, sometimes within 48 hours of hitting the streets, according to the Annex Network.

Hastings Police Chief Bryan Schafer said that vulnerability crosses his mind each time he sees one of the city's roughly half dozen chronic runaway kids and teens.

"We can't do this alone," he said.

State officials are meanwhile offering training sessions focused on combating sex trafficking for police officers across the state through Dec. 10 and an October conference in Brainerd will be aimed at investigators, prosecutors and child protection attorneys.