The probe committee formed to investigate the collapse made has come up with the findings.

Workers detected the cracks about 16 hours before the building caved in and immediately reported the matter to the higher authorities of the Shahriyar Fabrics Industries Ltd and the Spectrum Sweater Industries Ltd, according to an official source.

"But no step was taken to evacuate the building or to have it inspected by an expert. Instead, workers were asked to continue production to meet a deadline for export," the source said.

The five-member committee is scheduled to submit its report today.

A top-level member of the committee, requesting anonymity, told The Daily Star that the building collapse was the result of various causes, among them the fact that "the owners built nine storeys on a foundation approved for four storeys".

According to official sources, the seven owners of the company had received a huge order worth over Tk 20 crore from a European country. They urgently needed space to expand their facility to cope with the order and immediately decided to convert the four-storey building into a nine-storey structure without seeking an approval.

"The four-storey capacity foundation immediately became vulnerable with a dead load of an additional five storeys," the source added.

In addition, hundreds of industrial sewing machines and other machinery weighing several tons, which should have been installed on the ground floor, were instead placed on the top floors.

"The live load of machinery made the entire structure further vulnerable to collapse and 'horizontal vibrations' from their use resulted in cracks in the columns and foundation," he said.

The probe committee also concluded after its initial examination of the concrete slabs that the "concrete was of very poor quality".

"Now we want to test the foundation and the piling of the building, but it will not be possible until the debris is completely removed from the site," said the probe committee member.

He added that the committee sent samples of the materials to a laboratory for testing. The results might take time, the source said, but once they are obtained the prosecution against the culprits will be easier to start.

Inspector Khorshed Alam, the Detective Branch (DB) officer heading the investigation of the tragedy, recently said his focus is securing the test reports of the construction materials.

"Once I have the test reports of the construction materials, I can properly determine whether it was the neglect of the owners of the company or not," Inspector Alam said.

He added that no arrest warrant has been issued against the owner of the nine-storey building.

Alam explained that efforts to question the owner of the building have so far proved unfruitful. "I have asked the Gulshan thana to question the owner of [the factory], Sayeed Shahriar, but the police could not trace him at his residence," said Alam, adding that Sayeed Shahriar would be detained for questioning anywhere he is found.

Other DB sources said the seven owners of the two companies responsible for the collapse are too influential to be questioned.

Officer-in-charge of Savar Police Station Nazrul Islam filed a case on April 12 under the clauses of 338\304 Ka of the Bangladesh Penal Code, implicating the owners of the company in 'murder with negligence'. The case was immediately transferred to the Detective Branch.

The nine-storey building in Palashbari, Savar crumbled in the early hours of April 11, burying hundreds of unsuspecting workers working the night shift. Rescuers, led by army personnel from the Engineering Core, pulled out at least 61 bodies from the rubble, as well as 85 wounded workers.