(AP) -- Japan is already wild for Apple's latest iPhone.
Pre-orders began Tuesday at 5 p.m., and the early rush for the iPhone 4 led to long lines around Tokyo and overwhelmed computer servers struggling to keep up with demand.
Customers were instructed to submit reservations online with Softbank Mobile Corp., the iPhone's exclusive carrier in Japan, or at any of its retail outlets. Japan's seven Apple Stores were also taking pre-orders ahead of the June 24 launch.
Japan - along with the U.S., U.K., France and Germany - will be among the first countries where the iPhone 4 will go on sale. The latest model will feature a higher-resolution screen, longer battery life and thinner design.
At Softbank's flagship store in Tokyo's trendy Harajuku district, the line drew several hundred people who waited hours to place their reservations.
Steve Nagata, a Japan-based tech consultant and Apple enthusiast, said Tuesday evening that he had been standing in line for more than two hours and expected to be there another hour. He spent part of his time broadcasting the lively scene on the website Ustream.
"This is just showing how out of control this is getting," said Nagata, who owns both the iPhone 3G and 3GS. "It's just going to be a huge launch."
At the Apple Store in the upscale Ginza district, about 200 people were waiting in line shortly before dark. A similarly long line formed nearby at major electronics chain Bic Camera, which quickly ran out of pre-orders allotted for Tuesday. Instead, it began distributing tickets for the next day's reservation queue.
Meanwhile, repeated attempts to access Softbank's online store were unsuccessful.
Softbank spokesman Furuya Katsuhide said that the better-than-expected demand had stressed the company's systems, which slowed both its website and the reservation process at stores.
The Tokyo-based company does not release numbers, but Katsuhide said Softbank was thrilled with the "tremendous response."
When the iPhone was first released in Japan in 2008, skeptics questioned whether the country's mobile masses would embrace a device that lacked many high-tech features common on Japanese cell phones. But the iPhone has been a hit for Softbank, helping Japan's No. 3 mobile carrier lure customers from rivals and spurring broader interest in smart phones.
Under the threat of rain, Megumi Kawanishi stood outside Bic Camera for more than an hour to grab a spot in Wednesday's pre-order line. The 24-year-old said she decided to make the switch to an iPhone after more than a decade with NTT DoCoMo, Japan's largest carrier.
Kawanishi said she likes the iPhone's Internet capabilities, which would come in handy during overseas trips.
"This is a really long line, but I guess we need to stand in it to get an iPhone," she said. "It's like Disneyland."
Explore further: Indiegogo project 'Switchmate' lets you run light switch from your phone without rewiring