NATIONALIST politicians in Northern Ireland were last night urged to

tighten their personal security arrangements.

The firebombing of the homes of two SDLP councillors in south Belfast

has heightened fears for their safety from loyalist paramilitaries, who

have already murdered six times in just over a month.

A UVF assassination squad led by a man known as King Rat is suspected

by some Catholic sources of shooting the latest victim, 29-year-old

Eugene Martin.

Mr Martin, a Catholic, was killed on Tuesday night beside his home in

Ballyronan, near Magherafelt in County Derry.

Some politicians, increasingly worried by the scale of bloodshed, have

demanded that police form a special task force to catch the UVF gang. It

has been blamed for as many as 3O deaths since 1988.

The Rev. William McCrea, a Democratic Unionist MP who knew Mr Martin,

has demanded tougher Government action against the gunmen on all sides.

Security chiefs are deeply apprehensive. The level of loyalist

violence, much of it indiscriminate, is rising steadily.

In Tuesday night's incendiary attacks on the two councillors, the work

of the Ulster Freedom Fighters, Dr Alasdair McDonnell and Mrs Doria

Field escaped unhurt and damage was confined to the front of both

houses. Mrs Field is one of the few Protestant members of the SDLP.

According to the UFF, the attacks were carried out to mark yesterday's

meeting in London of the UK-Irish Conference, when the Northern Ireland,

Secretary Sir Patrick Mayhew, had talks on the security crisis with the

Irish Foreign Affairs Minister, Mr Dick Spring.

A UFF statement said: ''This is a small reminder that their party's .

. . stance with Sinn Fein has not gone unnoticed.''

Politicians on all sides are taking extra precautions in the light of

the latest specific warning.

One senior politician -- living behind high-wire fences, electronic

doors, bullet-proof glass, and five surveillance cameras -- admitted:

''Short of sitting up all night waiting for something to happen, there

is really not much else you can do.''