Here is the latest Iowa news from The Associated Press at 2:40 a.m. CDT

IOWA CITY, Iowa (AP) — The University of Iowa dental school is apologizing for accidentally exposing more than 100 child patients to potentially unsafe levels of nitrous oxide. The school says 124 patients who underwent procedures at its pediatric dentistry clinic between March 1 and April 20 face an “extremely small risk” of suffering any health effects. A school official says the university is unaware of what any long-term effects would be, but that it wanted to be cautious, nonetheless.

PITTSBURGH (AP) — Prosecutors say DNA and surveillance video prove a Pittsburgh man robbed and killed his neighbors _ two sisters of an Iowa state lawmaker. But the attorney for 45-year-old Allen Wade says he’s the victim of a “sloppy investigation” and a rush to judgment. Wade faces the possible death penalty if convicted of killing Sarah and Susan Wolfe inn February 2014, the sisters of Democratic Iowa state Rep. Mary Wolfe.

MASON CITY, Iowa (AP) — A 24-year-old man has died in a Mason City house fire that was started by unattended food cooking on a stove. Mason City Fire Department officials say Ackhasenh Cavan died as a result of the accidental Sunday morning blaze. Firefighters found Cavan outside the house when they arrived. He was given medical aid before being taken to a Mason City hospital, where he was declared dead.

STRAWBERRY POINT, Iowa (AP) — Officials say two students have been taken to a hospital after an eastern Iowa school bus was involved in a crash. The crash happed just before 8 a.m. Monday on Iowa Highway 3, west of Strawberry Point. Starmont School officials say a car driven by a student crashed into the back of the bus carrying 35 students. The driver of the car and a student on the bus were hospitalized.