SPRINGFIELD, Mo. -- Heroin is a growing problem in southwest Missouri, and police in Springfield are targeting dealers as a way of combating the problem.

Sgt. Justin Gargus of the special investigation unit of Springfield police told the Springfield News-Leader that as recently as 2011, investigators seized 13 grams of heroin for the entire year. In 2014, 243 grams were seized.

The unit has responded to more than 100 incidents involving heroin in 2014, up from 34 in 2011.

Springfield police are seeking out dealers, and Gargus said, when possible, authorities are seeking prosecution at the federal level.

As for users, Gargus said police are working to start a program putting first-time users in rehabilitation programs rather than jail. Staffing shortages have delayed implementation of that program.

Gargus said heroin is increasingly inexpensive. Many people who abuse prescription pills are finding it more difficult to get them, so they turn to heroin as a replacement.

But the purity level of heroin has risen dramatically in recent years. Many users are caught off-guard by the high level of purity, and an injection can be fatal.

Gargus said gang connections bring heroin to Springfield from Chicago. The original source of the drug is overseas, not Mexico, he said.

Today's users are the stereotypical junkies of the past, Gargus said. More than half are ages 18 to 30. In Springfield, 74 percent of users are white.

Gargus said there is a connection between the increase in heroin use and the increase in crime in the Springfield area, as users turn to crime to help feed their habit.

Information from: Springfield News-Leader, http://www.news-leader.com