Families descended from islanders evicted from the Chagos Islands are being housed in council-allocated accommodation deemed by social services to be inappropriate for young children, the Observer has learned.

The latest revelations prompted fresh calls for an independent investigation into the treatment of British Chagossians, forcibly removed by the UK in the 1960s and early 70s to allow the US military to establish a base on the largest island, Diego Garcia.

Last month the Observer revealed British passport holders from the Chagos Islands were being systematically targeted by council officials to get them removed from the UK. Now it has emerged that British Chagossians in Crawley, West Sussex, are being accommodated in lodgings about which social services have expressed serious concerns.

A West Sussex county council social services document, seen by the Observer, cites the case of a child living in a Crawley hotel, location of a sizable community of British Chagossians. “I am worried there are ongoing housing issues which impact on [name] having a safe and appropriate space to grow and support his development,” the document, written by a social worker, states.

The child, who turns three next month, has lived in the hotel all his life despite the accommodation being classed as temporary. Other Chagossian families with young children also claim they have been stuck there for several years. They say white British tenants are prioritised and usually given social housing after a few weeks or months.

Calls are mounting for an inquiry into the attitude of UK authorities towards the community with local Tory MP, Henry Smith, writing to Crawley borough council “expressing significant concerns at disturbing reports in the Observer”.

Chai Patel, legal policy director at the Joint Council for the Welfare of Immigrants said: “We need an independent investigation into how the government has been able to put these families in this appalling position, and what steps are needed to ensure it never happens again?

“The government needs to act now to ensure that these families are able to continue their lives in the UK safely and securely. It’s the least that it can do.”

The Chagossians were expelled from their homeland by Britain and exiled in Mauritius and the Seychelles, 2,000km away. In 2002 native Chagossians and their children were given the right to British passports and since then more than 3,000 have emigrated to the UK, most of them settling in Crawley.

One of them, a mother, has begged Crawley borough council to find her more suitable accommodation and says that her family finds it difficult to live in a single room.

“It’s not an easy life. Crawley council say they can’t help me. Even when I was pregnant, they didn’t want to help,” she said.

Another British Chagossian and former resident claimed the hotel, which declined to comment, was “not safe … there are men living there with drink and drug problems.”

While Crawley council denies reports of mistreatment, the council’s leader, Peter Lamb, has said they have investigated claims of discrimination from the Chagossian community but they were not acted on due to insufficient evidence.

Crawley borough council said: “Unlike the housing act, which limits family stays in hotel accommodation to six weeks, there is no limit under the children’s act. This may explain why those families have been there for an extended period of time, and may also explain why others are being reported to have moved on more quickly. We take complaints very seriously and all are thoroughly investigated.

“We are genuinely committed to getting to the bottom of these allegations and take appropriate steps if found to be true.”

During a meeting set up last year to air grievances from the town’s Chagossian community the council spokesperson added: “We were informed that on occasion housing officers were unsympathetic to their situation, unfriendly and considered unhelpful. The council apologised if this was how officers were behaving, and a commitment was made to raise the matter with the housing department to ensure that such behaviours were addressed.”

A West Sussex county council spokesman said: “In some circumstances we support families with children who have urgent housing needs. When this happens we make every effort to find a suitable placement. As temporary accommodation is not best suited to meet longer term needs, we work with a family to identify accommodation that meets the children’s needs as soon as we can.”