New Delhi | Two people and a juvenile, who was "the main shooter" in the GTB Hospital firing incident where a 32-year-old man was shot dead, were arrested here on Thursday, officials said.

According to the officials, the juvenile and the two accused -- Foujan (20) and Saif (19) -- killed Riyazuddin in a case of mistaken identity in ward number 24 of the hospital on July 14.

"All three, along with their one more associate, went to GTB Hospital and killed Riyazuddin, mistaking him for notorious criminal Waseem," Deputy Commissioner of Police (Shahdara) Surendra Choudhary said.

The DCP said the two accused and the juvenile were nabbed from northwest Delhi’s Brahampuri area.

"They were planning to flee the city. The main shooter is a juvenile, who frequently posts photos and videos posing with pistols on his social media accounts to gain followers," Choudhary said.

"All three are highly aware of technical surveillance and often resort to internet calls while planning or executing crimes. The shooter (juvenile) disclosed that he received a call from one Anas, who informed him about the Waseem gang's involvement in the murder of their common friend, Faiz.

"Anas also told them about the threats and abuses that were directed at Faiz's brother, Allu, by Waseem and his gang members while they were all in the jail," DCP Choudhary said.

The officer said that the juvenile was also angered by an attack on Kaif, another brother of Faiz, with a blade allegedly by Waseem gang members. In response, Anas hatched a plan to attack Waseem, who was admitted at GTB Hospital and was "deemed vulnerable", the DCP said.

"Anas provided them with two pistols, four magazines and 19 rounds of ammunition. The juvenile took one pistol and two magazines loaded with five rounds each, while another shooter took the other pistol with one magazine holding five rounds and another with four rounds. On the morning of the incident, Foujan surveyed the hospital to assess the situation," Choudhary said.

Following this, another accused Faiz, who was arrested from Loni in Uttar Pradesh on Monday, provided them with a motorcycle, the DCP said. Foujan, Saif, the juvenile and their associate, Shavej, used this motorcycle to reach GTB Hospital, where Foujan identified Waseem's ward, he added.

"The juvenile entered the ward and fired the first shot at the targeted person but his pistol got jammed before he could fire the second shot. Subsequently, another shooter fired three shots from his pistol. To ensure that their targeted person was dead, the juvenile repaired his pistol and fired another round. Throughout this, Saif stood guard at the ward's gate," the DCP said.

So far, six people, including one juvenile, have been nabbed in the GTB Hospital firing case, he added.

On Wednesday, Delhi Police arrested Moin (19), whom they identified as one of the key conspirators in the case, as he had conducted recce of the hospital for four consecutive days before the incident.

Earlier, the police on Monday nabbed two accused -- Faiz (20) and Farhan -- but said they did not fire the shots on July 14 evening, but provided logistic support to the main accused. Farhan was arrested from Delhi's Chauhan Banger area.