A Singapore Civil Defence Force (SCDF) officer has been sentenced to one month's jail for deleting video footage of fellow firefighter Kok Yuen Chin, 22, being pushed into a pump well during a ragging incident in May.

Adighazali Suhaimi, 33, a staff sergeant, was sentenced yesterday after pleading guilty to intentionally obstructing the course of justice by deleting evidence relevant to criminal investigations into Corporal Kok's death.

He is the second SCDF officer to be sentenced for his involvement in the drowning of the full-time national serviceman (NSF) on May 13 at Tuas View Fire Station.

The first was SCDF regular Muhammad Nur Fatwa Mahmood, 34, who was sentenced to 12 months' jail on Oct 23, after he admitted to the fatal push that resulted in Cpl Kok falling into the pump well and drowning.

Nur Fatwa, a staff sergeant, was also sentenced to four weeks' jail for instigating Adighazali to delete a video recording of the incident on his phone before the police arrived.

Three other SCDF officers also face charges in relation to the case.

Deputy Public Prosecutor Kumaresan Gohulabalan urged the court yesterday to sentence Adighazali to a jail term of at least one month, similar to what Nur Fatwa received for instigating the removal of the video. He said the duo had similar overall culpability and should receive similar sentences.

He said both were aware there would be investigations into the fatal incident, adding: "Despite the seriousness of this, they came to the agreement to delete the video."

In mitigation, Adighazali's lawyer Ashwin Ganapathy asked for a jail term of no more than 14 days, arguing that his client's culpability was lower than Nur Fatwa's.

He said Adighazali did not plan to delete the video and had done so under pressure, and that his client had confessed to deleting the video during the first police interview.

However, DPP Kumaresan said Adighazali confessed to deleting the video only after police found the footage in the deleted folder of his mobile phone.

District Judge Chay Yuen Fatt said he did not agree that Adighazali's role was of lower culpability. He also did not accept that Adighazali acted under pressure, saying: "He was acting out of a moment of self-preservation and cowardice."

The night of Cpl Kok's death began in festivity, with a group of officers - including Adighazali, Nur Fatwa and those charged - gathered to celebrate his impending operationally ready date on May 16.

A plaque and cake were presented to Cpl Kok, a permanent resident from Malaysia. The ragging ritual, which would involve him entering the pump well, was suggested.

Despite Cpl Kok's efforts to stop them, he was carried to the well by fellow officers. He drowned after being pushed into the well. His body was pulled out 36 minutes later.

Cpl Kok's father, construction worker Kok Meng Hwa, 56, was in court yesterday with the NSF's aunt. They also witnessed Nur Fatwa's sentencing in October.

Mr Kok said it was painful to hear the court rehash the events leading up to his son's death, saying he might not turn up for the next hearing.

When asked how he and his family were faring he said: "Life goes on... but my son won't come back."