Japan's two main airlines have grounded their Boeing 787 Dreamliners after one was forced to make an emergency landing because of battery problems.
All Nippon Airways (ANA) grounded its fleet of 17 Dreamliners when its flight NH 692 from Yamaguchi Ube was forced to land shortly after take-off.
Japan Airlines followed suit, saying it would ground its fleet of seven 787s from 16 January until further notice.
This is the latest setback for Boeing and its problem-hit Dreamliner planes.
On Wall Street, shares in Boeing closed down more than 3% following the Japanese announcements on Wednesday.
In recent weeks, Dreamliners have suffered issues including fuel leaks, a cracked cockpit window, brake problems and an electrical fire.
"You're nearing the tipping point where they need to regard this as a serious crisis," said Richard Aboulafia, a senior analyst with the Teal Group in Fairfax, Virginia.
"This is going to change people's perception of the aircraft if they don't act quickly."
On Wednesday, ANA's flight NH 692 left Yamaguchi Ube in western Japan at 08:10 local time (23:10 GMT) and headed for Tokyo's Haneda airport.
Earlier reports that smoke was seen in the cockpit were inaccurate, ANA said. The pilots saw a warning on their computer screen telling them there was smoke inside one of the electrical compartments, the airline said. The source of the smoke is not yet known.
The pilots also received a warning that there was a fault in the battery system. ANA said the battery in the forward cargo hold was the same type as the one involved in a fire on another Dreamliner at a US airport last week.
The ANA flight landed at Takamatsu airport at 08:47 on Wednesday after the pilot saw an error message in the cockpit.
"There was a battery alert in the cockpit and there was an odd smell detected in the cockpit and cabin, and [the pilot] decided to make an emergency landing," said Osamu Shinobe, an ANA vice president, at a news conference.
ANA said that the 129 passengers and eight crew were evacuated, with a number of people sustaining minor injuries.
The Reuters news agency reported that five people were injured, while Bloomberg said that one person was sent to hospital. ANA officials were not immediately available to confirm the figures.
The BBC's correspondent in Tokyo, Rupert Wingfield-Hayes, said that local television footage showed emergency chutes were deployed from the plane. There were also fire trucks on the runway.
Paul Lewis, a spokesman for Boeing, told the BBC that the planemaker was "aware of the diversion of a 787 operated by ANA to Takamatsu in western Japan".
He added that Boeing "will be working with our customer and the appropriate regulatory agencies".
Dreamliner's technical problems
8 Jan 2013: Take-off aborted after about 150 litres of fuel spill from Japan Airlines Dreamliner in Boston
13 Jan: Same aircraft experiences another, separate fuel leak while undergoing tests in Tokyo
4 Dec 2012: A United Airlines 787 makes emergency landing in New Orleans after electrical problems
13 Dec: Qatar Airways 787 grounded after electrical power distribution problems
17 Dec: United finds electrical problem in second aircraft
7 Jan 2013: Fire starts in lithium ion battery pack of Japan Airlines 787 in Boston
8 Jan: United Airlines also finds faulty wiring to battery
July 2012: Fan shaft on engine fails during runway tests at Charleston International Airport
11 Jan 2013: Oil leak found in engine of All Nippon Airways 787 flight
9 Jan 2013: All Nippon Airways cancels flight when computer wrongly reports a brake problem
11 Jan 2013: Cockpit window on an All Nippon Airways Dreamliner cracks during a Japanese domestic flight. The plane lands safely with no injuries
15 Jan: Another Dreamliner operated by ANA makes an emergency landing at Takamatsu in Japan after a smoke alert goes off
The concerns have spread beyond Japan, however, not least because the Dreamliner was seen as Boeing's flagship new aeroplane and had attracted orders from many of the world's biggest and best-known airlines.
The 787 is said to be one of the most fuel-efficient in the industry, and Boeing delivered 46 Dreamliners to customers in 2012.
Following Wednesday's landing, India's aviation regulator said it would review the Dreamliner's safety and talk to parts makers.
The regulator said it was in contact with Boeing but as yet had no plans to ground the six Dreamliners that are currently being used by Air India.
Australia's Qantas Airways said its order for 15 Dreamliners remained on track. Its subsidiary Jetstar is due to take delivery of the first of its aircraft in the second half of this year.
United Airlines is the only US carrier currently flying Dreamliners, and the carrier said it was not taking any immediate action.
Even before Wednesday's emergency landing, Boeing was facing an inquiry by Japanese and US authorities over its Dreamliner issues.
Last week, the US Federal Aviation Administration started a joint review with Boeing of the design, manufacturing and assembly of the Dreamliner.
On Tuesday, Japanese authorities said they would conduct an inquiry after two successive fuel leaks on a different 787 operated by Japan Airlines.
On 8 January, Japan Airlines reported that a fire broke out on a 787 shortly after it landed in Boston. There have also been reports of brake issues.
"It is not abnormal for new aircraft to have some teething problems," said Chris de Lavigne of Frost and Sullivan in Singapore.
"There were initial issues with the Airbus A380 as well. Look where it is today; it is flying successfully and everyone seems to be happy with it."
However, he added that a lot would depend on the outcome of the two investigations.
"If it turns out to be a major issue and requires re-engineering to be done, then you may need to ground some of the planes or even the entire fleet."