“This is a region that has already been devastated by war and a country that knows suffering all too well,” Saltmarsh said.
He pointed out that even before the air strikes, there had been significant displacement from southern Lebanon.
“The situation is extremely alarming. It is very chaotic,” he said.
“The toll on civilians is unacceptable.”
Monday’s attacks came after an Israeli strike on southern Beirut on Friday killed dozens, including two senior Hezbollah commanders. Days earlier, coordinated communications device blasts that Hezbollah blamed on Israel killed 39 people and wounded almost 3,000.
Since last week, nearly 6,400 people had been injured in Lebanon, according to the WHO.
“The hospitals have been crazy challenged in managing the number of injuries since last week,” WHO’s representative in Lebanon, Abdinasir Abubakar, told reporters.
Speaking by video from Beirut, he said more than 90 percent of the wounds suffered last week when pagers used by Hezbollah exploded across Lebanon “are on the face and limbs, especially hands”.
“Many people had both eye and hand injuries, which required two different sets of operations,” he said.
“This is not normal,” insisted Ravina Shamdasani, spokeswoman for the UN rights office.
“When you have people losing their eyes and when you have hospitals not able to cope with the amount of amputations that they need to carry out … (it) is extremely abnormal.”
She said the rights office was “extremely alarmed by the sharp escalation of hostilities”, calling on “all parties to immediately cease the violence and to ensure the protection of civilians”.
The UN children’s agency decried the impact on young people in Lebanon.
“We are warning today that any further escalation in this conflict will be absolutely catastrophic for all children in Lebanon,” said Ettie Higgins, UNICEF deputy representative in Lebanon, speaking from Beirut.
“Yesterday was Lebanon’s worst day in 18 years. This violence has to stop immediately, or the consequences will be unconscionable.”