AT&T has said it will buy T-Mobile USA from Deutsche Telekom AG in a cash-and-stock deal valued at $39 billion that would make it the largest cellphone company in the US. The deal would reduce the number of wireless carriers with national coverage from four to three, and is sure to face close regulatory scrutiny.

Analysts at Barclays and UBS had speculated that shutdowns at Mitsubishi Gas would deprive some chipmakers of a chemical resin used to package their products, causing supply disruptions.

A spike in radiation levels at Japan's stricken Fukushima nuclear plant has forced workers to suspend their operation, a government spokesman says.

Rumors circulated that Apple may have chosen to TSMC as their new fab in response to new competition from Samsung in the handset and tablet space. Based on analysis performed by UBM TechInsights Lab and Process Analysis personnel, we can say that the A5 in our possession is definitely manufactured by Samsung using their 45nm process.

Shares and other risky assets from the Australian dollar to commodities such as copper and oil slumped on Tuesday while safe-haven assets like US Treasuries rallied as Japan's nuclear crisis worsened.

Sony has announced that, following the devastating earthquake and tsunami that struck the northern region of Japan on March 11, Sony and its group companies will donate JPY300 million (US$3.66 million) to help relief and recovery efforts in communities affected.

Brent crude fell by almost US$3, reaching a two-week low near US$111 on investor pessimism that economic growth will slow in the wake of Japan's earthquake and tsunami, while easing unrest in the Middle East threw the focus back onto ample oil supplies.

The devastation in Japan is set to worsen the negative short-term sentiment gripping a vulnerable US stock market, with companies exposed to Japan and the nuclear energy sector likely to take the biggest hits.

A second explosion has hit the nuclear plant in Japan which was damaged in Friday's earthquake, but officials said it had resisted the blast.

Apple's next-generation iPad contains chips made by Toshiba, Broadcom and Texas Instruments, according to an initial tear-down report by gadget-repair site iFixit. Toshiba supplied the device's storage chips, iFixit said, while Broadcom made the chips used for wireless Internet access. TI chips were used to control the iPad's touchscreen.

Japan's biggest-ever earthquake halted production briefly at Toshiba's chip plants on Friday and could delay crucial shipments. Toshiba and SanDisk share cutting-edge facilities in Yokkaichi, where they make NAND chips increasingly in demand by Apple and other mobile device makers.