After thieves broke into his garage in June and stole an expensive bicycle, Nathan Clough bought a replacement and hung it in the garage, wrapping a thick metal chain around it for added security.

A month later, he had only the remnants of the chain — his new bike was gone, too.

“The police told me that after this, they would suggest I keep the bike in the house,” said Clough, who paid two $1,000 deductibles to his insurance company.

South Minneapolis is in the grips of a sharp rise in burglary cases this summer, fueled largely by increased garage break-ins and thefts of high-end bikes. Records show that 721 burglaries have been reported to police so far this year in south Minneapolis, a 16 percent increase over this time last year.

The dramatic increase is setting off a stream of complaints from homeowners and small businesses, another blow for a part of the city already reeling from a sharp increase in violent crime, particularly robbery. Burglary can be a leading indicator of broader increases in criminal activity and is a crime that is far more likely to impact and aggravate city residents.

“People are definitely feeling the effects and the impact, and they’re wondering what’s going on,” said Ninth Ward City Council Member Alondra Cano, who has attended five community meetings on public safety in her ward this year. “What I’ve seen the most is people interested in figuring out how to solve it.”

The burglary spree comes as the latest bad news for south Minneapolis. A rash of robberies has pushed up violent crime in the area by 13 percent, the sharpest rise of any area in the city this year. Police Chief Janeé Harteau said Wednesday that she will have four extra police officers work overtime shifts in south Minneapolis until Labor Day as part of a $300,000 plan to fight a summer crime wave.

Among the most recent burglaries, thieves are vastly preferring garages over houses, clearing out bicycles, motorcycles and other items.

In one incident, a burglar smashed a car window and used the garage door opener to walk into the garage and nab a bike. On Monday evening, a woman in the 2500 block of 28th Avenue S. said someone walked into her house while she was home, grabbed her wallet and fled. Last Friday, someone walked into the back door of a duplex in the 3100 block of Chicago Avenue S. while the resident and his 5-year-old son sat in the living room. The burglar was surprised to see the residents, shouted “Amigo, no problem,” and left. The victim discovered his wallet missing.

In one recent case, thieves broke into a garage only to get nothing. The garage had already been picked clean by another burglar.

Police do get occasional breaks in some cases.

In June, they broke up a high-end bicycle theft ring in which they discovered 44 bikes stuffed into the basement, living room and attic of a house on Bloomington Avenue S. A man who lived there had been selling the stolen bikes on Craigslist, police alleged.

Clough, who had his orange road bike worth nearly $2,000 lifted from his garage last week, said he suspects the thief knew exactly what he or she was looking for. “They forced open the [service door] window, reached around and unlocked the door, cut the chain, and stole that bike and left my wife’s bike there,” he said.

The thief quietly severed a heavy-duty chain that Clough and a hardware store clerk could not break when he was shopping for the toughest lock possible.

Meanwhile, Stephen Meyer noticed a strange-looking bike near his garage last week. He thinks whoever left it there was the same person who broke into his garage and rode off on his mountain bike. “They did an exchange,” he said.

Brandon Wells, marketing coordinator for the Hub Bike Co-op in south Minneapolis, said the shop has had a lot of customers calling for serial numbers after their bikes were stolen. “This year, especially, we’ve seen an inordinate number of calls about that,” he said of bike thefts.

Police say residents need to ensure that they’re doing all they can to deter burglars.

Of the eight burglaries reported to Third Precinct Inspector Michael Sullivan last week, four were cases in which burglars walked through unlocked service doors or open overhead garage doors. He urged homeowners to lock their doors and to install lighting on the garage.

To make it even harder to break into a garage, install brackets on the inside of the service door to hold a 2-by-4 across it when it’s closed. Even if the lock fails, the door cannot easily be opened with the 2-by-4 in place.

Authorities are beefing up patrols, too. Sullivan said he has directed patrol officers to do “alley sweeps,” looking for suspicious persons. The precinct also has done specific patrols targeting areas where they see a pattern of break-ins.

Police cannot do it alone, Sullivan said. He noted that the Bloomington Avenue bike-theft case was broken open by a witness who called 911 after seeing something suspicious.

“Our best bet in catching these criminals is when they’re in the act,” he said.