Wikipedia gives "Alan Bell (1858-1920), Magistrate and member of the British Secret Service. Taken off a Dublin tram and executed by the IRA." He apparently was appointed to a secret committee on intelligence in Nov. 1919. Dwyer said he was running Byrnes and a number of other agents, and reported directly to Basil Thomson. Thornton's Witness Statement says he was sent to Ireland in early 1920 as a special investigator to examine every account in every Bank of Ireland with the object of tracing and seizing the Dail funds, as these funds were spread across many names and many accounts
The Squad by Dwyer, says that an Irish American newspaper reported the following Sept "a rather colourful story that Bell had arranged for a Scotland Yard detective to go to Mountjoy prison, pose as a priest and hear confessions of political prisoners there. The IRA supposedly learned of this and shot both Bell and the detective the next day. The fact that no DMP detective was killed in the whole month of March was not allowed to get in the way of a good story" In fact Molloy was murdered on 24 March and Bell on 26 March. I suspect Molloy is the other man referred to here.
Resident Magistrate Alan Bell, from Banagher, had been tasked by the British to track down Collin's war chest. By the 26th of March 1920, he had successfully confiscated over £71,000 from Sinn Féin's HQ and, by investigating banks throughout the country, was set to seize much more. On that day he was pulled off a tram in south Dublin and shot three times in the head.
On March 3 armed military raided the Women Workers' Club, the Irish Women Workers' Union, Liberty Hall, the Socialist Party of Ireland headquarters, the Grocers' Assistants' Union headquarters, and the Irish Drapers' Assistants' headquarters - all in Dublin. At the same time Alderman Wm. O'Brien, the leader of the Irish Labour movement, was snatched away and smuggled into England, where he was kept in prison without trial. Immediately after that it was learned that on March 1, 1920, Mr. Alan Bell had commanded high bank officials to appear at the Police Court, Inns' Quay, Dublin, with all books and documents used in their banks, so that they might be examined by Government officials. The purpose was to trace all Sinn Fein moneys, and also to know all the business of prominent supporters of the Sinn Fein cause so as to crush them down to poverty. Bell issued the summonses as Resident Magistrate for the County of Dublin.
Republican literature says that he first appeared as an assistant to Jas. E. French, chief of the English Secret Service in Ireland. As a result of Wm. O'Brien's exposures in 1884 of Dublin Castle immorality, French was convicted of "un natural crime". Bell was said acted as his agent-provocateur in the West of Ireland in the Land League times, one of his exploits being the arrest of Henry George, author of Progress and Poverty, during his visit to Ireland in the eighties.
They also say Bell was the secret agent of the London Times during the Piggott forgeries' case, in which Piggott confessed he had been bribed to forge the handwriting of Parnell so as to involve Parnell in high treason. And that since then Bell carried on his work as an English spy in Ireland. The attorney-general withdrew the letter on behalf of The Times, and the commission pronounced it to be a forgery. Shortly after the letter had been withdrawn, Parnell filed an action against The Times for libel, claiming damages to the amount of £100,000. The action was compromised without going into court by a payment of £5000.
After Bell's death, Constable Harry Kells of B Div., DMP, with 20 years service, was promoted to Detective Constable and assigned to the Crime Section of G Division. Kells was carried out identity parades at Mountjoy Prison trying to find out who had executed Alan Bell. On 13 April Clancy received a note signed M.C. advising that the writer would be going to Kells tomorrow. The next day members of Collins’ “Squad” caught up with Harry Kells and shot him as he was walking down Camden Street on his way to work, A passing motorist brought Kells, who had been shot through the chest, to Meath Hospital, but he was dead upon arrival.