UPDATE 6-Gaza rockets land deep in Israel as it bombards Palestinian enclave
* Palestinians say 53 dead in Gaza, mostly civilians
* Gaza rockets hit deeper inside Israel
* Violence along Gaza frontier is worst since 2012 (Updates casualties, Netanyahu says operation could take time, news agency reports Egypt to open Gaza border crossing; paragraphs 6, 10, 19, 31)
By Nidal al-Mughrabi and Jeffrey Heller
GAZA/JERUSALEM, July 9 (Reuters) - Israeli air strikes shook Gaza every few minutes on Wednesday, and militants kept up rocket fire at Israel's heartland in intensifying warfare that Palestinian officials said has killed at least 53 people in the Hamas-dominated enclave.
Missiles from Israel's Iron Dome defence system shot into the sky to intercept rockets launched, for the second straight day, at Tel Aviv, the country's commercial capital. Some were also aimed at Israel's Dimona nuclear plant, 80 km (50 miles) from Gaza, but were either shot down or landed in open country.
With cries of "Allahu akbar" (God is Greatest), Palestinians in the Gaza Strip cheered as rockets streaked overhead toward Israel, in attacks that could provide a popularity boost for Islamist Hamas, whose rift with neighbouring Egypt's military-backed government has deepened economic hardship.
Dimona, desert site of a nuclear reactor and widely assumed to have a role in atomic weaponry, was targeted by locally made M-75 long-range rockets, militants said. The Israeli army said Iron Dome shot down one and two others caused no damage. It was unclear how close they came to the town or the nuclear site.
Communities near coastal Tel Aviv and in the south, closer to Gaza, were also targeted. In the longest-range attack since Tuesday, when Israel stepped up its offensive, a rocket hit near Zichron Yaakov, a town 115 km (70 miles) north of Gaza. Continued...