It was around this time that his relations with his neighbors began to deteriorate, and his resentment grew over what he regarded as "derogatory remarks made about my character". The evening prior to the killings, he went to a movie theater in Philadelphia, where he sat through several shows before returning home about 3 a.m. He had gone to the theater to meet a homosexual man for a date, but was delayed and the man was gone by the time he arrived. It was the following morning that he decided to commit the rampage. Both his brother, James, and his father Samuel, indicated that Howard's wartime experiences had changed him, making him moody, nervous and detached, although James also pointed to the ongoing feud his brother had been having with his neighbor, the pharmacist Maurice Cohen, as a possible trigger for the killing spree. For several months he had been engaged in a dispute with Cohen relating to use of the pharmacist's backyard as a means of access to his apartment. As well as Cohen, he planned to kill John Pilarchik, shoemaker, Clark Hoover, barber, and Thomas Zegrino, tailor.