It appears that one of the latest two detainees is linked to Alejandro's "aunt" and "uncle" (his stepfather's siblings), who have now been released on bail. According to Alejandro's family, this detainee also lived at the same address as two of the initial suspects.

The new arrests took place hours after the National Police deployed from Madrid returned on Wednesday to the young man's home for another search.

Unlike the operation three weeks ago, this time the police did not use heavy machinery. The search focused on a thorough examination of rooms, walls, floors, nooks and crannies and areas around the back garden to find biological remains or any clues that might help locate the young man.

During the previous operation, the police's search focused on the back garden of the property, where the couple with whom Álex was living had apparently put up a wall to create a sort of room for him.

The investigators dug into the floor of this room, where they allegedly found the young man's belongings, including some items of clothing and a briefcase in which, according to his neighbours, he used to keep a flute.

The police's main theory at the time of the first arrests was that the body might be hidden beneath the house: a suspicion backed by the testimony of several neighbours, who claimed that the inhabitants had carried out work in the back garden following the disappearance under the pretext of "burying a dog".

After appearing before the court, the four suspects were released on bail, although they remain under investigation in connection with the case.

Alejandro had moved in with his "aunt and uncle" after leaving his mother's flat, which was just two floors above in the same building. According to neighbours, the young man was often seen outside various supermarkets, playing the flute to beg for money and help support the household.

Although the initial investigation suggested he might have left of his own accord, Álex's immediate family believe he would not have left on his own without leaving a note. The investigators have also found this suspicious since the very beginning.

For more than two years, one of the main suspects, the woman Alejandro called "aunt", repeatedly turned to the media and social media asking for help in locating him.

In March, the National Police also carried out a large-scale operation in the area in an attempt to track down Alejandro. The operation focused on an area of 31,000 square metres, where, among other locations, the Ronda recycling centre, an abandoned house, a former landfill site and a pine forest were searched.

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