Iranian twins conjoined at the head die.

Fifty grueling hours into an unprecedented operation to separate adult twins conjoined at the head, Dr. Keith Goh's heart sank.

He was working furiously Tuesday to save Laleh Bijani, who began bleeding profusely the moment surgeons made the final cut to separate her from her sister, Ladan.

Gone was the sound of classical music that played the day before. The small room was mostly silent except for the surgeons' instructions and the beeps and pulses of the monitors.

Then Goh glanced over at Ladan. She was losing blood even faster.

The 29-year-old Iranian twins died shortly thereafter - Ladan at 2:30 p.m. and Laleh 90 minutes later. Both were still under anesthesia.

''I was very saddened,'' said Goh, the lead surgeon. ''I saw them struggling - of course at the same time we were struggling too.''

In their homeland, Iranians cried out in shock or wept as state television announced the deaths of the twins from a poor family who touched the world with their determination to lead separate lives - and to see each other face-to-face, rather than in a mirror.

''Is my beloved Ladan really not with us anymore?'' Zari, an elder sister, told The Associated Press after the first death was reported in Iran. Seconds later, she fainted.