Crime declined on the whole in St. Tammany Parish in 2015 compared with the prior year, officials said, with only the city of Slidell showing what the police department there described as a small increase.

St. Tammany Sheriff Jack Strain said crime in unincorporated parts of the parish was the second-lowest in a five-year period. Violent crime fell by 2 percent, and while there were three killings in 2015, homicides were in the single digits for the eighth year in a row.

There were no homicides in Mandeville or Covington, according to police there. Slidell had one homicide in 2015 — a newborn baby whose body was found in a trash compactor. There were no homicides in Slidell in 2014.

Randy Smith, Slidell’s police chief and St. Tammany’s sheriff-elect, said overall crime in his jurisdiction was down 28.6 percent since 2006.

Slidell showed an increase in robberies, with 19 in 2015 compared with 15 in 2014, and assaults rose from 53 to 70. Thefts also were up, with 1,279 in 2015 compared with 1,213 a year earlier. Auto thefts fell from 57 to 39.

Strain reported that burglaries in unincorporated St. Tammany are on a downward trend with 314 reported in 2015, a five-year low. Thefts and auto thefts showed an increase, he said.

In Covington, Chief Tim Lentz reported a decrease in every crime category, with 510 crimes in 2015 that met the criteria for reporting under the FBI’s Uniform Crime Reports, down from 549 in 2014. Motor vehicle accidents accounted for more calls for service than crimes, he said.

Mandeville had two reported rapes in 2015 compared with none in 2014. Thefts were up from 219 to 247, and auto thefts were up sharply, with 12 in 2015 compared with four in 2014. Mandeville saw decreases in assaults and burglaries. It had two robberies in 2015, the same as in the prior year.

Follow Sara Pagones on Twitter, @spagonesadvocat.