UN Secretary General Ban Ki-moon has condemned a fatal Israeli attack on a humanitarian aid convoy en route to the impoverished Gaza Strip.

"I condemn this violence," Ban said on Monday. "It is vital that there is a full investigation to determine exactly how this bloodshed took place."

"I am shocked by reports of killings and injuries of people on the boats carrying supplies," said the UN chief.

The Israeli navy stormed the Freedom Flotilla earlier on Monday, killing at least 20 people, mostly Turkish nationals and injuring 50 others, al-Aqsa television reported.

The convoy was intercepted by the Israeli navy in international waters, some 150km (90 miles) off the coast of the Gaza Strip.

The killing of international activists by the Israeli military has faced condemnation across the world.

Turkey, which led the nine-vessel convoy, along with several European countries, denounced the Israeli navy’s move and called for an emergency meeting of the United Nations Security Council over the incident.

Sweden, Greece, Spain, Denmark, Norway, Italy, Belgium, France, Germany, and Ireland have all summoned Israeli envoys to their respective countries.

Bulgaria’s foreign ministry sought to confirm the whereabouts of two Bulgarian journalists traveling on the Gaza-bound flotilla.

In Egypt, President Hosni Mubarak denounced Israel’s use of "excessive and unjustified force" on the humanitarian aid convoy.

The United States also expressed sympathy with the bereaved families, saying it deeply regretted the deaths and injuries of the incident.

The convoy was carrying 10,000 tons of supplies and hundreds of politicians, activists and journalists.

The Flotilla was seeking to break Israel’s crippling blockade of Gaza and deliver basic necessities to the impoverished Palestinians living in the coastal enclave.

(Press TV)