The man accused of killing Fahim Saleh, a 33-year-old tech entrepreneur who was found dismembered in his apartment, pleaded not guilty to a second-degree murder charge on Sunday.

CNN reported that attorneys for 21-year-old Tyrese Haspil encouraged the public to keep an open mind when it came to whether Haspil was guilty. Police said Saleh’s cousin interrupted the killer while they were attempting to clean up the murder scene. The killer fled before the cousin walked into the apartment and discovered Saleh’s remains.

“We are in the very earliest stages of ferreting out the truth. The life of this case promises to be long and complex. As the attorneys for Mr. Haspil, we urge the public to keep an open mind,” the attorneys said.

The killer followed Saleh into an elevator, then assaulted him with a Taser after the doors opened on the floor of his apartment, according to security footage recovered by officers. The killer then reportedly stabbed Saleh several times before decapitating him.

Haspil, who was employed as Saleh’s personal assistant, has no prior criminal record, authorities said, according to CNN. A potential motive for the killing was not immediately clear, according to police, but Haspil is thought to have owed Saleh thousands of dollars. His next court appearance is in August.

Saleh is a co-founder of Gokada, a motorbike hailing service based in Lagos that was the first of its kind to operate in Nigeria, one of Africa’s fastest-growing tech markets.