Tshamano alleged some were caught with guns while leaving the church premises.
"We are sitting with two versions - that of the investigating officer and that of the accused. The accused said they were arrested when they arrived at the church. The State witness stated that [some of the accused] were arrested leaving the church premises carrying firearms. This attack was planned."
He said another group of the accused "were part of the group that went inside the church. Accused number 22, who owns a security company, was also arrested with a group leaving the church.
"Accused number one to 18 all worked for accused number 22. They [accused one to 18] were not going to work as they claimed, but to join others inside the church."
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Regarding a firearm found inside a Toyota Quantum, Tshamano said the accused were aware of it.
He added the firearm, whose serial number was filed off, was not concealed or hidden inside the vehicle.
The court earlier heard the Toyota Quantum, which was occupied by 14 of the suspects, was reportedly stolen in KwaDukuza in KwaZulu-Natal in August last year.
Investigating officer Sergeant George Maditse said the police had confiscated several vehicles outside the church, including the Toyota Quantum that reportedly transported the accused to the church.
Magistrate Gavin Pillay is expected to rule on the accused's bail application on 11 August.