They said it was “not a transgression” and that the Chinese army personnel came to the Indian side due to varying perception of the Line of Actual Control – the de facto border between the two countries.
The sources said the incident took place around July 25.
A source in Itanagar said Lok Sabha MP from Arunachal Ninong Ering wrote a letter to Prime Minister Narendra Modi about the incident, quoting media reports and inputs given by locals in Dibang valley.
In the letter, he suggested that the government should take up the issue of “Chinese transgressions” in Arunachal Pradesh with Beijing.
A group of Chinese army personnel intruded around 300 metres into the Demchok area in eastern Ladakh and pitched four tents in the area in July.
They came to the Indian side of the border in the garb of nomads and pitched the tents. The Chinese army personnel later left the place after India protested against it.
Officials said such transgressions are not unusual as there were varying perceptions of the LAC by both China and India.
India regularly takes up all such incidents at the appropriate level with Chinese authorities.
India and China share a nearly 4,000-km-long border.
The number of “transgressions” by the Chinese army into the Indian territory rose to 426 in 2017 from the 273 in 2016, according to official figures.
Indian and Chinese troops were locked in a 73-day standoff in Doklam last year. The face-off had ended on August 28 last year.