*

Network disruptions are fully restored, Verizon says

*

Chicago and Seattle among hardest-hit cities, iPhone users

stuck

in 'SOS' mode

*

Outage began at 9:30 am ET, peaked at 105,000 reports by

11:19

am ET, according to Downdetector.com

By Harshita Mary Varghese, David Shepardson

WASHINGTON, Sept 30 (Reuters) - Verizon has fully

restored a network disruption that impacted thousands of

customers in the U.S. The Federal Communications Commission said

earlier on Monday it was investigating the company's network

outage across the U.S. after thousands of users reported

outages.

Verizon said in a statement later on Monday that the service

has returned to normal levels.

Chicago and Seattle were among the hardest-hit cities and

some iPhone users were stuck in "SOS" mode.

According to the tracking website Downdetector.com, the

outage began at around 9:30 a.m. ET and there were 28,842

reports as of 5:02 p.m. ET, with regions including Minneapolis,

Phoenix, Omaha and Denver among the most reported areas being

affected.

Verizon Communications ( VZ ) said earlier in the day that

its engineers were making progress on the network issue and

service has started to be restored.

"We apologize for any inconvenience some of our customers

experienced today," Verizon said, without providing further

details on the reason behind the outage.

There were about 105,000 reports around 11:19 a.m. ET, at

the peak of the outage, according to Downdetector.com.

The FCC said it was "working to determine the cause and

extent of these service disruptions."

Some Verizon users said on social media platform X that

their phones were stuck in "SOS" mode.

"SOS" appears in the status bars of iPhones if the device is

not connected to a cellular network but can still make emergency

calls through other carriers, according to Apple's ( AAPL )

website.

The outage tracking website also showed 448 incident reports

by AT&T ( T ) users as of 5:15 p.m ET, but the carrier said it

was not experiencing a nationwide outage and the network was

operating normally.

"Downdetector is likely reflecting challenges our customers

are having attempting to connect to users on another network,"

AT&T ( T ) said.

Sector rival AT&T ( T ) faced nationwide wireless outages in February

that lasted over 12 hours and impacted more than 70,000

customers.

The FCC is investigating the AT&T ( T ) outage, which blocked more

than 92 million voice calls and prevented more than 25,000

attempts to reach 911, the agency said.

News of the Verizon outage came hours after the company

announced a deal to give infrastructure firm Vertical Bridge

rights to lease, operate and manage 6,339 mobile towers across

the U.S. for $3.3 billion.