A convicted child sex offender has been sent back to prison after police uncovered more child sexual abuse images — while a separate secure folder on another phone remained locked behind a code he refused to reveal.

Mattie Tomassen, 34, of Furnace Bank, Carmarthen, was jailed for 26 months at Swansea Crown Court after admitting possessing indecent images of children in categories A, B and C, and breaching a Sexual Harm Prevention Order.

The court heard Tomassen had already been jailed for similar offending and was subject to restrictions imposed following his previous conviction.

Police visited his accommodation on March 19, 2026, acting on intelligence, and arrested him on suspicion of possessing indecent images.

Officers seized a Motorola phone, and Tomassen provided its PIN. An initial examination found no images, but investigators discovered a secure folder requiring a separate access code.

Tomassen refused to provide it. He claimed the folder might have been installed before he bought the phone and said he had never used it.

Police subsequently contacted the Argos store where he purchased the device. The retailer confirmed it sold only new phones and did not deal in reconditioned devices.

Investigators also discovered a message in which Tomassen referred to having material in his secure folder, telling a contact: “This looks like one in my secure folder.”

Police remained unable to access the folder, leaving its contents unknown.

Tomassen was arrested again on July 9 after e-Safe monitoring software on another phone alerted police that he had repeatedly accessed X, formerly Twitter, and viewed child abuse material.

A forensic examination recovered 12 images depicting the sexual abuse of boys, including two classified as Category A — the most serious category.

The court heard the images had been deleted or remained in the phone’s cache and were no longer accessible to the user, although they would previously have been accessible.

Tomassen answered “no comment” during questioning but supplied the PIN for that device.

His record included two previous convictions covering six offences, including possession of indecent images in June 2025 and threatening to destroy property in December that year.

Judge Huw Rees instead imposed consecutive prison terms of 14 months for the images and 12 months for breaching the order. Both sentences included a one-third reduction for his guilty pleas.

Tomassen was also made subject to a new 10-year Sexual Harm Prevention Order and must remain on the sex offenders register for the same period.