A Derby man charged in the death of his girlfriend and the wounding of her son waived his right to a preliminary hearing.

An attorney for 40-year-old Charles A. Beck Jr. entered not guilty pleas Wednesday for Beck on charges of first-degree murder and attempted murder.

Beck is charged in the Sept. 1 strangulation of 44-year-old Lonnie Staggs at her Derby home. Prosecutors say Beck also tried to strangle Staggs’ teenage son but he was able to lock himself and an 11-year-old sister in another room.

Beck turned himself in shortly after the deaths in Texas County, Mo. The Wichita Eagle reports he is being held in the Sedgwick County Jail on a $1 million bond.