CODENAME KILINDINI: A Top-Secret Code-breaking Operation

Written by | Quick Reads

From the outside, the Allidina Visram was a typical Indian boys’ school from April 1942 to August 1943. Inside though, the Asian institution was bustling with geeks, mathematicians and statisticians who formed the core of a covert code-breaking operation.

Allidina Visram School was built by his son Varas Abdul Rasul for about 50 thousand pound sterling, about 1.5 million pounds today. Abdul Rasul built it in memory of his entrepreneurial father, the great Varas Allidina Visram, after whom he named it. In some anecdotes, Rasul built the school because he lost a bet. It must have been an expensive bet because he used up most of his inherited wealth, or what was left from his other gambling losses, to build the institution. Every bit of the materials was imported from India, and the school was designed to accommodate 500 pupils.

For a whole year at the height of World War II, however, it was commandeered for covert activities. Seven years prior, in 1935, Bletchley Park, the headquarters of the Government Code and Cypher School (GC & CS) set up the Far East Combined Bureau in Hong Kong. The GC & CS and its successor were designed as an intelligence and security organisation that works closely with MI5 and MI6, as well as other security arms. It focuses on signals intelligence and information assurance.

Four years later, the bureau moved to Singapore. As the Japanese strangled Singapore City into surrender, the British code breaking intelligence arm scattered, with the Army and RAF code breakers moving to Delhi in India and the Navy ones to Colombo in Ceylon. The Navy code breaking unit, the J-Group, was followed by the Japanese bombs to its new base. As the Japanese began doing runs on Colombo, the entire British Eastern fleet hassled across the Indian Ocean to another British Colony, Kenya. The Coastal strip was then referred to as the Protectorate of Kenya, and Kilindini, Mombasa, was the ideal temporary base until the tides of war turned in Britains favour.

Image from

Image from

With the Eastern Fleets retreat came the J-Group, and the beginning of a fascinating story that broke the cipher of the Japanese merchant ship supply chain code. Upon arrival, the code breaking team was set up at a small hotel called Lotus. Meanwhile, the paymaster Lieutenant-Commander Harry Shaw requisitioned the Allidina Visram institution and designated it HMS ALLIDINA. A contingent of King’s African Rifles (KAR) was then deployed to guard the facility. They seem to have had a thing for Indian institutions as their former base in Ceylon, Pembroke College, was also an Indian boy’s institution.

In the fascinating fictional story, ‘Merchant of Mombasa the narrator is one of the J-Group code-breakers. The short fictional story covers her experience in Mombasa, specifically her promotion by Lord Braithwaite, the Commanding Officer (CO) of the British East Africa Command, so she could and negotiate with the shrewd Jewish businessman Abraham S. Talal for two rare-breed horses. The negotiation spawned off a relationship which eventually ended up in her getting pregnant and being discharged honorably, retired as wounded. Most parts of the story are fictional but the facts of the code-breaking outstation are pedantic.

The story begins with the words of a sign that supposedly stood in the school compound. Written in both English and Swahili, the sign said:

Loose lips sink ships
and will result in
severe disciplinary action.
By order: Braithwaite, CO,
East Africa Command ( Kilindini).

In September 1942, the code breakers broke the cipher for the core code used by the Japanese merchant ships, the JN-40. They followed this up with further successes, most of them which resulted in varied victories for the British Navy. The breaking of the codes JN-40, J-152 and JN-167 helped the British Navy monitor and attack Japanese supply lines.

The covert code breaking unit stayed at the school for 16 months, away from the public eye and working day and night to break the J-codes of the Japanese military.

In September 1943, the Royal Navy Code breakers went back to Colombo, to a new station on the Anderson Golf Club. With them left all evidence that the Asian school that overlooks the old Nyali Bridge had once been the temporary headquarters of an elite code breaking group.


One Story is Good,

Till Another is Told.


Last modified: April 26, 2017