"The accused (Xolile Mngeni) was actually insisting he would cooperate with police. He did not deny anything at that stage, in fact at any stage," Lt-Col Bonginkosi Kwinana told the court.
He and his fellow Hawks officers raided Mngeni's home in Khayelitsha early on November 16 2010, but he was not there.
They found him at a nearby shack in the same street and arrested him with another man and two women.
Mngeni has pleaded not guilty to hijacking, robbing and killing Dewani in Gugulethu on November 13 2010. She was on honeymoon with her husband Shrien at the time.
Kwinana said that when they entered the shack Mngeni was sleeping on a bed with two women and another man.
The officers, in civilian clothes, produced their identification and arrested Mngeni after reading him his rights.
A search of the shack revealed a cellphone wedged between the base of the bed and the mattress.
"Captain Paul Hendrikse then asked: 'Who does this cellphone belong to?' His (Mngeni's) response was: 'It belongs to the taxi driver," Kwinana said.
The four were driven to the Hawks' office in Bellville. It was then that Mngeni told the officer he wouldcooperate.
When they arrived at the Hawks' building, Kwinana took Mngeni into his office so they could chat alone, since Mngeni was compliant and the officer did not want the other members to intervene.
"I asked if he knew anything about the case. He said yes, he knows about the case. He then gave me the name of the other accomplice who was actually with him."