Guwahati, India - Police in Indian state of Assam has accused an army veteran, who served the country for 30 years, of being an undocumented migrant and asked him to prove his nationality in a Foreigners Tribunal court.

The Foreigners Tribunal, established to detect illegal citizens residing in India, has issued a notice in the name of Mohammad Azmal Haque, 49, who retired from Indian Army as Junior Commissioned Officer (JCO).

The notice said that Haque had entered the country after March 25 of 1971 without any papers - the cut-off date to be considered for Indian citizenship.

It further said if Haque thinks otherwise, he needs to be present at the court in Kamrup district with proper documents to prove if he is an Indian.

"I was shocked and stunned. I never expected this kind of treatment after serving the nation for 30 years. I gave everything for my country. I had taken pledge to put my country first before anything else when I joined the army and I take pride in it," Haque told Al Jazeera.

The notice was issued on July 6 this year. As it arrived late at his residence, he missed the date on September 11. Now he is expected to appear in the court on October 13.

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"But this is something I never expected. It's humiliating," a sobbing Haque, told Al Jazeera, from his residence at Chaygaon, in Kamrup district of Assam state, in the northeastern part of India.

Haque who joined the Indian Army in 1986 said that all his documents were verified by police before he was inducted into the army.

"Besides, my father Maqbul Ali's name features in the 1966 voters' list. If my parents are Indian and if all my siblings are Indian, how can I be an illegal foreigner? I'm very hurt at this treatment," said Haque whose elder son is studying at Rashtriya Indian Military College (RIMC) and aspires to be an army man.

Incidentally, his wife Mamataj Khanam was also served notice in 2012 when Azmal was still serving in the army. However, it was sorted out later in the court.

"This is nothing but harassment. How many times we need to prove our citizenship?" asked the army veteran.

Indian defence official, Lieutenant Colonel Suneet Newton, said that Haque will be provided all required assistance.

"We have learnt of the matter and we are looking into the details, the required assistance will be provided to the individual," Newton said.

Assam Director General of Police Mukesh Sahay also said that he will look into the matter why the notice was served to the former army officer.

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Aman Wadud, Haque's lawyer, said that his client was never approached by any investigation agency.

"He (Haque) is being accused as 'illegal immigrant' without any investigation whatsoever. If a person who served Indian Army for 30 years can be harassed and humiliated in this manner you can imagine what normal citizens go through.

"This is the story of hundreds of thousands of genuine Indian citizens in Assam who are being harassed and humiliated on daily basis in the name illegal immigrants," Aman told Al Jazeera.

Earlier this year, Abu Taher Ahmed, a policeman himself, was also served notice as an illegal citizen. Though, he was cleared later.

According to the government data there are altogether 141,733 doubtful or 'D' voters present in Assam. People who are marked as 'D' voters are not allowed to vote and their citizenship rights, entitlements and privileges are withheld until they prove their citizenship.

An official document published by Assam government in October, 2012 says that more than 92 percent of the resolved cases of 'D' voters have been declared as genuine Indian nationals.