NAIROBI (AFP) - Police in Kenya said Thursday they were holding 77 Chinese nationals accused of running a cyber crime network and mysterious "command centre" from upmarket houses in the capital Nairobi.

Kenya's foreign ministry has also summoned China's top diplomat in Nairobi as it seeks to establish if Beijing was in anyway linked to the affair.

Kenyan police said they believed the gang was "preparing to raid the country's communication systems".

The Daily Nation newspaper said a series of police raids had turned up equipment capable of infiltrating bank accounts, Kenya's M-Pesa mobile banking system and ATM machines.

"The suspects are being interrogated to establish their mission in the country and what they wanted to do with the communication gadgets. They have been charged in court," said the director of Kenya's Criminal Investigation Department, Ndegwa Muhoro.

"We want to do a thorough investigation over the matter and we are currently working on their travel documents," added police spokeswoman Zipporah Mboroki.

Police said many of those detained appeared to have been in the country illegally.

A detective close to the case said the raids were sparked after police began investigating a house fire that left one person dead.

The source said the charges levelled against the 77 so far include "being in the country illegally and operating radio equipment" without the necessary permits.

According to the Standard newspaper, the Chinese nationals were living in "military-style dormitories".

China's ambassador to Kenya was summoned to "explain if his government was aware of the group's activities".

Kenyan foreign minister Amina Mohamed "made it clear that the Chinese government should fully cooperate on this matter," Kenya's communications minister Fred Matiang'i said.

"China promised to send investigators to work with ours on this matter," he said, adding the case "is being investigated by the police working closely with the foreign ministry".

The Standard newspaper said preliminary investigations have shown the group were making microchips for ATM cards, and that they also "ran a command centre whose activities are yet to be established".

The homes were reportedly located in the upmarket northern Nairobi suburb of Runda, which is located next to the diplomatic area of Gigiri, home to the United Nations' headquarters and US embassy.

The affair is a rare visible sign of tension with China, a major investor in Kenya's infrastructure and communications networks and hailed earlier this year by President Uhuru Kenyatta as "an honourable partner" for east Africa's largest economy.