A plastics manufacturer in India has expressed concern that its products were used to carry explosives in an attempted terror attack in the UK.
Police say the containers could provide 'vital clues'
The head of Family Plastic and Thermoware in the southern state of Kerala said that he had spoken to British police about the containers.
He said it was "unfortunate" the firm's Delta storage containers had been used.
Four men tried unsuccessfully to detonate bombs on three London Tube trains and a bus on Thursday 21 July.
All the devices were placed within the same type of plastic food storage containers, each six-and-a-quarter litres in size with a white lid, which were then put in dark-coloured rucksacks.
They were labelled "Delta 6250" on the lids and had a label reading "family containers Delta superior quality".
British police traced the boxes to India and discovered that they had been made by Family Plastic and Thermoware, which is based in Thiruvananthapuram in Kerala.
The company's managing director, Simson Fernandes, said he had been approached by British police to confirm that the plastic boxes had been made by his firm.
He said that he had supplied information to them on where the boxes were distributed in the UK.
Police traced the containers to the Indian state of Kerala
"It is just a coincidence," Mr Fernandes told the Press Trust of India. "It is unfortunate that our jar has been used for carrying bombs."
He said that the company exported its products to several countries, including the US, South Africa and Dubai.
The containers were available in many shops in London, he said.
British police have appealed to retailers in London to search their memories and come forward if they can remember anyone looking suspicious who purchased the containers.
They have said any information in relation to them could provide "vital clues" in the search for the would-be suicide attackers.
Correspondents say "Delta" food containers are popular for storing pulses and rice and are found in about 100 retail outlets in the UK, most of them run by British Asians.
Retailers in north-west London say they sell hundreds of the containers every month, often in multi-packs, and it would be impossible to remember everyone who bought them.
The "Delta" boxes are made out of sturdily-built transparent plastic, and come with lids in different colours.
Correspondents say the fact that Indian products are in the spotlight has one again focused media attention on Britain's Asian community.
Three of the suicide bombers who blew themselves up on London's underground network and a bus on 7 July were of Pakistani descent.