UPDATE: Tunisia beach resort massacre kills 37

Tunisia--

A man pulled a gun hidden in a beach umbrella and opened fire at a packed Tunisian holiday resort Friday, massacring 37 people in the country's worst attack in recent history.

The carnage at the popular Mediterranean resort of Port el Kantaoui came the same day as a suicide bomber killed 25 people at a Shiite mosque in Kuwait and a suspected Islamist attacked a factory in France.

There was no immediate claim of responsibility for the Tunisia attack, but the Islamic State group, which marks the first anniversary of its "caliphate" straddling Iraq and Syria Monday, said it was behind the Kuwait bombing.

Witnesses described scenes of panic after the shooting at the Riu Imperial Marhaba Hotel on the outskirts of Sousse, about 140 kilometres (87 miles) south of Tunis.

The health ministry gave the toll at 37 dead.

"There are 37 dead and 36 wounded. Some of the wounded are in a critical condition," ministry communications chief Chokri Nafti said, revising an earlier toll of 28 dead.

A spokesman for Spain's RIU group, which runs the five-star hotel, said most of the 565 guests were from Britain and "central European countries".

In Dublin, Foreign Minister Charles Flanagan said an Irish woman was among the dead.

Interior ministry spokesman Mohamed Ali Aroui told AFP "a terrorist attack" targeted the hotel.

"The assailant was killed," he added, without ruling out the possibility of accomplices.

Secretary of State for Security Rafik Chelly told Mosaique FM the gunman was a Tunisian student unknown to the authorities.

"He entered by the beach, dressed like someone who was going to swim, and he had a beach umbrella with his gun in it. Then when he came to the beach he used his weapon," Chelly said.

- 'Bullets whizzing' -

The shooting was the worst in modern-day Tunisia and followed a March attack on the Bardo National Museum in Tunis that killed 21 foreign tourists and a policeman.

IS claimed responsibility for the Bardo attack, although Tunisia says it was carried out by an Algerian jihadist.

Gary Pine, a British holidaymaker, said Friday's shooting happened at around midday (1100 GMT) when the beach was thronged.

"Over to our left, about 100 yards (metres) or so away, we saw what we thought was firecrackers going off," he told Britain's Sky News television.

"Only when you could start hearing bullets whizzing around your ear do you realise it was something a lot more serious than firecrackers."

Pine said panic spread quickly.

"There was a mass exodus off the beach," said Pine, adding he heard 20 or 30 shots.

"My son was in the sea at the time and of course my wife and myself were shouting for him to get out the sea quick and as we ran up the beach he said: 'I just saw someone get shot'."

Holidaymaker Susan Ricketts said people were "running and screaming... crying and going hysterical".

Dubliner Elizabeth O'Brien told Ireland's RTE radio she also heard what she thought was fireworks before realising it was gunfire.

"I ran to the sea to my children and grabbed our things and, as I was running towards the hotel, the waiters and the security on the beach started shouting 'Run, run, run'," she said.

The tourist area was later completely sealed off by security forces, a witness said.

- 'Be vigilant' -

The French embassy in Tunis urged its nationals to be vigilant and to "limit travel and avoid gatherings".

President Francois Hollande of France and his Tunisian counterpart Beji Caid Essebsi both expressed their "solidarity in face of terrorism", a French statement in Paris said.

Essebsi later told AFP Tunisia cannot stand up to the jihadist threat alone, and urged a unified global strategy.

In Cairo, a leading Sunni Muslim institution called the "heinous" shooting a "violation of all religious and humanitarian norms".

Tunisia, the birthplace of the Arab Spring, has seen a surge in radical Islam since veteran president Zine El Abidine Ben Ali was ousted in the 2011 revolution.

Dozens of members of the security forces have been killed in jihadist attacks since then.

In October 2013, a suicide bomber blew himself up in a botched attack on a beach in Sousse while security forces foiled another planned attack nearby.

Even before the latest attack, Tunisia's tourism industry had been bracing for a heavy blow from the Bardo shooting, but was determined to woo tourists with new security measures and advertising.

Tourism Minister Salma Rekik announced a raft of measures to bolster security in tourist areas and roads leading to them, and to tighten airport controls.

The tourism sector, which accounts for seven percent of Tunisia's GDP and almost 400,000 direct and indirect jobs, had already been rattled by political instability and rising Islamist violence.